Cabbage, Broccoli, Cauliflower, and Other Brassica Crops

Introduction

The term "cole crops" refers to waxy-leaved brassicas of European origin, of the species Brassica oleraceae. Cabbage, broccoli, and cauliflower and other brassica crops are hardy crops that are well adapted to New England. Plants maturing under cool weather conditions are of especially high quality. This diverse family has similar cultural requirements, diseases, and pests.

Types and Varieties

• Cabbage is the most widely grown and easily cultivated of the brassica crops. Some varieties mature in as few as 60 days or as many as 120 days from transplanting. The early and mid-season varieties are generally better suited for fresh market sales where small heads of 3-4 lb are desired. 
• Cauliflower is more difficult to grow than other brassica crops. Common problems include failure to head properly and poor curd quality. For successful production of cauliflower, a fertile, moist soil relatively high in organic matter and nitrogen is needed. Buttoning is the premature formation of the head, when the leaves are not large enough to produce a head of marketable size. Conditions that reduce the vigor of the plant and retard vegetative growth, such as cold temperatures at transplanting and any of a number of other stresses appear to encourage buttoning. Cauliflower varieties range in maturity from 55 to 95 days.
• Broccoli is not as exacting in its requirements as cauliflower. However, it must be harvested promptly to avoid flowering. The earliest spring plantings often experience buttoning. In summer months, temperatures over 85° F during the critical period when the head begins to form can result in poor head quality. In southern New England, broccoli is best grown as a fall crop. Broccoli varieties range in maturity from 55 to 75 days.
• Brussels sprouts are a long season crop grown for harvest in the fall.  Brussels sprouts should be harvested when they are round, firm, tight, and of good color. Brussels sprout varieties range in maturity from 90 to 110 days or longer.
• Kale is cold-hardy and grows best as a fall crop when grown for full-size leaves, but can be succession-planted all season. Kale is also commonly grown as a component of salad mix (see Salad Mix Section). The flavor of the leaves is improved after a light frost.
• Kohlrabi looks like a turnip growing on the top of the ground with sprouting leaves over the surface. Most varieties must be harvested when to 3" in diameter or they can become tough, especially in spring production. Fall storage kohlrabi varieties can be grown to 6" in diameter. 
• Chinese cabbage (Brassica napa), Mustard (Brassica juncea) and Bok choi (Brassica rapa var. chinensis), are grown as salad or braising greens and as heading crops. They have non-waxy leaves and most are Asian in origin. See Salad Mix section for more details on production of salad mix. Crops in this group are more susceptible to damage from flea beetles, but tend to be less attractive to caterpillars than waxy brassica crops. When grown as heading crops, these should be direct seeded from early May to mid-July depending on intended harvest date and location in New England. Chinese cabbage is especially sensitive to bolting in response to stress or cold. Nitrogen management for Chinese cabbage should differ slightly from other brassica crops (see Soil Fertility below).

Many other brassica greens, such as mizuna, mibuna, tatsoi, komatsuna, arugula, and mustard are usually direct seeded. Some varieties are prone to premature flowering, which is enhanced by cold temperatures in the spring. Transplanting, which is less common than direct seeding, can also increase premature flowering in the spring due to increased plant stress. Plant densities vary tremendously and should be geared toward the intended harvest age and size.

Brassica Crop Varieties

Resistant or tolerant to: BR: black rot, CR: clubroot, DM: downy mildew, TB: tipburn, Y: yellows

Soil Fertility

Apply lime according to soil test to maintain soil pH at 6.5-6.8. Maintain a high level of calcium to minimize tip burn.

The best method to apply a small amount of boron is as an additive to the fertilizer. For example, if the level of boron in the soil is low, apply 3 lb/A of B (15 lb Solubor, or 30 lb Borax) before planting broccoli and cauliflower, and 2 lb/A for cabbage. See Tables 6 and 6a.

For Chinese cabbage, pepper spot can develop on the stalks of the plants as a result of excess nitrate uptake. Apply only 50 lb of actual nitrogen at planting and sidedress additional nitrogen at diminishing rates as the plant nears harvest maturity, for a total of 150 lb/A. Foliar or drip applications scheduled at 6 to 8 lb per week may be the most practical.

Less nitrogen fertilizer will be needed if legume sod was plowed down or if manure was applied (see Table 1 and Table 7).

If using transplants, use of a liquid starter fertilizer at planting time is beneficial, especially with cool soil conditions. Use a high phosphorus starter fertilizer mixed at a rate of 3 lb per 50 gallons of water. Apply 8 fluid ounces (1 cup) per transplant.

Plant nutrition recommendation according to soil test results for Cabbage, Broccoli, Cauliflower, and Other Brassica Crops

*CAULIFLOWER APPLY 30 LBS/A

Planting and Field Culture

Early plantings of cabbage and other brassica crops are generally made by setting out transplants grown in greenhouses or cold frames. Transplants should be 5-7 weeks old at field setting. For cauliflower and broccoli, transplants should be produced in greenhouses with a minimum nighttime temperature of 50° F. Excessive cold, transplant stress, inadequate fertility, or other sources of stress in early stages can cause brassica crops to button, or to go to seed without heading. Transplants with thick stems are likely to head prematurely or button. Midseason and late plantings can be transplanted or direct seeded. If cabbage, broccoli or cauliflower are direct seeded, 2-3 weeks should be added to the number of days to maturity.

Generally, coarse-textured soils (sands, sandy loams, etc.) are favored for early plantings because they can be worked earlier in the spring and will warm up faster. These soils are also less likely to become waterlogged under rainy spring conditions. Finer-textured soils which have a greater water holding capacity can frequently be used to advantage for producing later crops. 

• Cabbage grown for fresh market should be planted to stand 12-15" apart within rows and 24-36" between rows. With most early or midseason varieties the closer spacing will give larger yields and smaller heads, which can be a more desirable size for fresh markets. Where direct seeding is used, seeding depth is 1/2-3/4". One-half to 1 lb of seed will be required per acre (0.125-0.25 oz per 100 feet of row) depending on variety, seed size, and spacing. Thin seedlings to desired stand when plants are 2-4" tall. Do not allow plants to become crowded.
• Cauliflower should be planted to stand 15-18" apart within rows and 30-36" between rows. Broccoli should be spaced according to market needs. Large single heads can be achieved by a 15-18" spacing. To acheive three-head bunches, which require 5-6" heads with small stalks, plant double row beds with 36" between beds and 10-12" between rows within bed, and 6-9" between plants, depending on variety. Early varieties usually require closer spacing. Southern grown plants can be purchased for transplants, but insect and disease problems often accompany them. If purchasing bare root transplants from nurseries, plant soon upon receipt. Field-grown transplants, once pulled, should not be stored for longer than 9 days at 32°F or 5 days at 66°F prior to planting in the field. Cauliflower and broccoli can be direct seeded to stand, with precision type planters. Raised beds of 4" are recommended. For cauliflower this will require about 4 oz seed per acre (0.0625 oz per 100 feet of row); for broccoli about 0.5 to 1 lb/acre (0.125 to 0.25 oz per 100 feet of row).
• Brussels sprouts are most commonly grown from transplants as a long season crop for fall harvest. Cool weather and light frosts prior to harvest increase quality. Rows are typically spaced 36" apart with 15" spacing within the row. Plants can be topped in early September, when 80% of the sprouts have reached marketable size, to improve sprout size uniformity if harvesting entire stalks. Stripping the foliage from the lower 1/2-2/3 of the plant will allow more light to reach the developing sprouts, as well as increase air circulation, both of which increase sprout quality.
• Kale can be successfully grown from direct seeding or from transplants. For direct seeding, sow seed at 3-4 lb/A in rows spaced 16-36" apart. Thin to 4-5"  apart in the row. Transplants are set in rows 16-36" apart and 6-12" apart in the row. Use wider between-row and in-row spacing for multiple hand harvests by stripping leaves. 
• Kohlrabi may be grown for spring crops by transplants. Transplant into the field at the same time as broccoli or cabbage. Fall crops can be established by direct seeding between June 25 and July 15. Seed open-pollinated varieties at the rate of 2-3 lb per acre and thin to 6-8" between plants in the row. Precision-seed hybrid varieties. Set transplants July 20 to August 15. Space rows 18-24" apart.

Irrigation

The availability of water can be critical for successful production. Adequate soil water must be maintained during seedling or transplant establishment and the period of rapid vegetative growth that follows. This is extremely critical prior to head initiation for cabbage, since excessive water applied after cabbage heads have formed can result in split heads. When harvest periods of broccoli and cauliflower occur during times of high temperatures, light irrigation (0.33-0.5") can be used to cool plants and help maintain quality. 

Harvest and Storage

• Cabbage. Harvest as soon as the head has reached full size for the variety grown. Many varieties will stand in the field for considerable periods of time after heading without serious deterioration, but harvest should not be delayed unnecessarily as plants become more susceptible to disease and to splitting.
• Cauliflower heads must be blanched in order to produce attractive white curd. Blanching refers to covering the developing cauliflower head in order to shade it from sunlight. Newer varieties are self-blanching or self-wrapping. Unless a variety is reported as being self-blanching, when the head is 2-3" diameter, gather the large outer leaves loosely over the head and tie with twine or rubber bands. Tie every 2-3 days with different colored bands to help coordinate harvest dates. Hot, humid, rainy weather after tying can result in a rotting curd. In hot weather, the head should be ready to harvest in 3-5 days; in cool weather, blanching takes 8-12 days. Harvest when head is compact, clear white and about 6" in diameter. Avoid bruising during harvest and packing.
• Broccoli is harvested when heads are dense and 3-6" diameter, and before individual flower buds are distinguishable or yellow flowers can be seen. Cut 8-10" of stem with the head. Broccoli should be cooled as rapidly as possible and stored under cool conditions after harvest to slow down flower development. Side heads develop rapidly following removal of the terminal head, unless the variety used is a nonsprouting type. Harvesting may continue for several weeks. Broccoli is especially sensitive to postharvest heat and should be hydrocooled or packed on ice immediately after harvest.
• Brussels sprouts should be harvested when sprouts are firm and are of the desired size for market. Sprouts can be harvested sequentially, working up the stalk as the season progresses, or entire stalks can be cut and marketed whole. 
• Kale and Collards may be harvested by cutting off entire plants near ground level, then bunching whole plants. Alternatively, mature leaves may be stripped from plants and either bunched or packed individually. Multiple harvests are possible. 
• Kohlrabi. The targeted harvest stage is when stems (bulbs) are full sized but before they begin to split or become tough ans woody. Bulbs are cut with clippers at the soil line, and foliage is trimmed as dictated by markets. Leaves should be removed for long storage varieties.

Many brassica crops are very sensitive to ethylene, and may yellow upon exposure to low levels of ethylene. These crops should be stored as close to 32ºF as possible without freezing, at greater than 95% relative humidity. Air circulation should be adequate to remove heat of respiration, but excessive air circulation will speed transpiration and wilting of leafy crops. Expected storage life varies widely. Consult USDA Handbook 66: The commercial storage of fruits, vegetables and florist and nursery stocks, for crop-specific information. 

Disease Control

NOTE: For the disease control products listed below, one product trade name and formulation is provided for each active ingredient (common name) as an example of rates, preharvest interval (PHI), restricted entry interval (REI), and special instructions. In many cases, there are other products available with the same active ingredient. Please see Table 25 and Fungicides and Bactericides Alphabetical Listing by Trade Name for more information on products with the same active ingredients.

The symbol ^OG   indicates a product is listed by the Organic Materials Review Institute (OMRI) as approved for use in organic production. See Organic Certification section for more details.

Alternaria Damping-Off

Buy seed certified as disease-free or treat with hot water at 122°F for 25 minutes (see Hot Water Treatment of Seed, in the Disease Management section). Brassica crop seed is susceptible to seed vigor loss from hot water treatment. Seed should be treated as close to planting as possible.

Alternaria Leaf Spot and Head Rot

Alternaria leaf spot and head rot are caused by at least three species of the fungus Alternaria and may be seedborne. Start with certified disease-free seed or treat seed with hot water. Practice a 3-year crop rotation with all brassica crops. Use proper plant and row spacing to ensure good air circulation. Irrigate in the morning. Avoid overhead irrigation if possible. Control weeds, especially those in the family Brassicaceae. Avoid working in fields when foliage is wet. Promptly incorporate plant debris after harvest, or mow if tillage is not possible in late fall crops. Varieties differ in susceptibility but no resistant varieties are available. 

• azoxystrobin (Quadris): 6.0 to 15.5 fl oz/A; PHI 0d, REI 4h, Group 11. Do not repeat the application or rotate with other strobilurins. See label for list of allowed brassica crops.
• azoxystrobin plus difenoconazole (Quadris Top): 12.0 to 14.0 fl oz/A; PHI 1d, REI 12h, Groups 11 & 3.
• Bacillus amyloliquefaciens strain D747 (DoubleNickel^OG): 0.25 to 3.0 lb/A; PHI 0d, REI 4 h, Group BM 02. Disease suppression only. For improved control; mix or rotate with a chemical fungicide.
• boscalid (Endura): 6.0 to 9.0 oz/A; PHI 0d, REI 12h, Group 7. Maximum 2 applications per year.
• botanical extract (Ecoswing^OG): 1.5 to 2.0 pt/A; PHI 0d, REI 4h, Group BM 01.
• chlorothalonil (Bravo Weather Stik): 1.5 pt/A; PHI 7d, REI 12h, Group M 05.
• copper hydroxide (Kocide 3000): 0.5 to 0.75 lb/A; PHI 0d, REI 48h, Group M 01.  Do not apply in a spray solution having a pH less than 6.5 or tank mix with Aliette.
• cyprodinil plus fludioxonil (Switch 6.25 WG): 11.0 to 14.0 oz/A; PHI 7d, REI 12h, Groups 9 and 12.
• difenoconazole plus cyprodinil (Inspire Super): 16.0 to 20.0 fl oz/A; PHI 7d, REI 12h, Group 3 and 9. Apply in sufficient volume to achieve thorough coverage. 
• fenamidone (Reason SC): 8.2 fl oz/A; PHI 2d, REI 12h, Group 11. Do not alternate with other Group 11 fungicides.
• flutriafol (Rhyme 2.08 SC): 5 to 7 fl oz/A; PHI 7d, REI 12h, Group 3.
• fluxapyroxad plus pyraclostrobin (Priaxor Xemium): 6.0 to 8.2 fl. oz/A; PHI 3d, REI 12 h, Groups 7 and 11.
• mancozeb (Manzate Pro Stick): 1.6 to 2.1 lb/A; PHI 7d, REI 24h, Group M 03. Cabbage and broccoli only.
• penthiopyrad (Fontelis): 14.0 to 30.0 fl oz/A; PHI 0d, REI 12h), Group 7.
• polyoxin D (OSO 5%SC): 6.5 to 13.0 fl oz/A; PHI 0d, REI 4h, Group 19.
• potassium bicarbonate (PB 133, AKA MilStop^OG): 2.5 lb to 5.0 lb/100 gal; PHI 0d, REI 1h, Group NC. See label for small volume application rates.
• Pseudomonas chlororaphis (Howler^OM): 2.5 to 7.5 lbs/A. PHI 0d, REI 4h, Group BM 02. Use preventatively. 
• pydiflumetofen plus fludioxonil (Miravis Prime): 11.4 fl oz/A; PHI 7d, REI 12h, Groups 7 and 12.
• pyraclostrobin (Cabrio EG): 12.0 to 16.0 oz/A; PHI 0d, REI 12h, Group 11.
• triflumizole (Procure): 6 to 8 fl oz/A; PHI 1d, REI 12h, Group 3.

Black Leg (Phoma lingam, Leptosphaeria maculans)

Symptoms of this fungal disease include grayish lesions with dark borders on leaves and stems. All brassica crops are susceptible. Rotate away from brassicas for at least 3 years. Start with certified, disease-free seed, or treat seed with hot water. Inspect seedlings for infection before planting out into the field. Use proper plant and row spacing to ensure good air circulation. Avoid overhead irrigation if possible. Control weeds, especially those in the family Brassicaceae. Avoid working in fields when foliage is wet. Promptly incorporate plant debris after harvest, or mow if tillage is not possible in late fall crops.

• fluxapyroxad plus pyraclostrobin (Priaxor Xemium): 6.0 to 8.2 fl. oz/A; PHI 3d, REI 12 h, Groups 7 and 11.
• iprodione (Rovral 4F): 2.0 pt/A; PHI 0d, REI 24h, Group 2. Broccoli ONLY.
• potassium bicarbonate (MilStop^OG): 2.5 to 5.0 lb/100 gal; PHI 0d, REI 4h, Group NC. See label for small volume application rates.
• pyraclostrobin (Cabrio EG): 12.0 to 16.0 oz/A; PHI 0d, REI 12h, Group 11.
• thiram (Thiram 42-S):  8 lb/A. Seed treatment; REI 24h, Group M3.

Black Rot (Xanthomonas campestris pv. campestris)

Symptoms of this bacterial disease include yellow to brown lesions, most often on the leaf margins. Some lesions will have a characteristic V shape and blackened veins. Practice a 3-year crop rotation with all brassica crops. Start with certified disease-free seed or treat seed with hot water. Use proper plant and row spacing to ensure good air circulation. Avoid overhead irrigation if possible. Control weeds, especially those in the family Brassicaceae. Avoid working in fields when foliage is wet. Promptly incorporate plant debris after harvest, or mow if tillage is not possible in late fall crops.

• acibenzolar-S-methyl (Actigard): 0.5 to 1.0 oz/A; PHI 7d, REI 12h, Group P 01. Suppression only.
• copper hydroxide (Kocide 3000): 0.5 to 0.75 lb/A; PHI 0d, REI 48h, Group M 01.  Do not apply in a spray solution having a pH less than 6.5 or tank mix with Aliette.
• mancozeb plus copper hydroxide (ManKocide): 1.0 to 1.75 lb/A; PHI 7d, REI 48h, Groups M 03 & M 01. Not labeled for cauliflower.
• Pseudomonas chlororaphis (Howler^OG): 2.5 to 7.5 lbs/A. PHI 0d, REI 4h, Group BM 02. Use preventatively. Not labeled for cauliflower.

Club Root (Plasmodiophora brassicae)

Initial symptoms include stunting, yellowing, and wilting. This disease is characterized by marked swelling and deformity of roots. There is currently no way to eliminate club root from infested soil, but the pathogen can be suppressed by practicing a long crop rotation and increasing soil pH. Maintain soil at a pH of 7.0 to 7.2 by applying lime a maximum of 1000 lbs/A per application. Practice a routine 3-year rotation for all brassica crops; if club root is detected in a field, rotate out of brassicas in that field for 7 years. After a 7-year crop rotation, pH adjustment and fungicide applications may reduce the viable club root spores to below economic threshold levels of infection for many growing seasons to come. Cold, wet soils favor club root development and spore survival. Resistant varieties of some brassica crops are available. Prevent the movement of infested soil and irrigation water into uninfested fields.

• cyazofamid (Ranman): 12.9 to 25.75 fl oz/100 gal (transplant drench); PHI 0d, REI 12h, Group 21. Tank mix with an organosilicone surfactant. Transplant soil drench or soil incorporation. See label for details.
• fluazinam (Omega 500 F):  6.45 fl oz/100gal (transplant drench); PHI 7-50d, REI 12h, Group 29. Transplant soil drench or incorporation. PHI varies by crop. See label for details.
• PCNB (Blocker 4F): Rate varies depending upon application method - see label; REI 12h, Group 14. For transplant applications, mix 3 pts into 100 gal water and use 0.5 to 0.75 pts solution per plant, based on severity of field infestation. Maintain agitation to hold product in suspension. For banded applications, apply as a 12-inch band, in 25 gal water per acre or 5.5 fl oz water per 100 ft of row based on 40-inch row spacing. For broadcast applications, apply in 30 gal water prior to planting. For all application methods, thoroughly incorporate into soil after application.

Downy Mildew (Hyaloperonospora brassicae)

Symptoms include angular yellow to orange lesions on the upper sides of leaves with dark sporulation on the underside. Resistant varieties of some brassica crops are available. Use proper plant and row spacing to ensure good air circulation. Avoid overhead irrigation if possible. Control weeds, especially those in the family Brassicaceae.  

• acibenzolar-S-methyl (Actigard): 0.5 to 1.0 oz/A; PHI 7d, REI 12 h, Group P 01.
• ametoctradin plus dimethomorph (Zampro): 14.0 fl oz/A; PHI 0d, REI 12h, Groups 45 and 40.
• azoxystrobin (Quadris): 6.0 to 15.5 fl oz/A; PHI 0d, REI 4h, Group 11.
• Bacillus amyloliquefaciens strain D747 (DoubleNickel^OG): 0.12 to 1.0 lb/A as a soil drench; PHI 0d, REI 4 h, Group 44. Suppression only. For improved control, mix or rotate with an approved chemical fungicide.
• chlorothalonil (Bravo Weather Stik): 1.5 pt/A; PHI 7d, REI 12h, Group M 05. See label for replant restrictions.
• copper hydroxide (Kocide 3000): 0.5 to 0.75 lb/A; PHI 0d, REI 48h, Group M 01. Do not apply in a spray solution having a pH less than 6.5 or tank mix with Aliette.
• cyazofamid (Ranman):  2.75 fl oz/A (foliar application); PHI 0d, REI 12h, Group 21. Tank mix with an organosilicone surfactant. 
• dimethomrph (Forum): 6.0 fl oz/A; PHI 7d, REI 12h, Group 40. Apply in combination with a labeled rate of another non-group 40 fungicide.
• fenamidone (Reason SC): 5.5 to 8.2 fl oz/A; PHI 2d, REI 12h, Group 11. Do not alternate with other Group 11 fungicides.
• fluazinam (Omega 500F): 15.35 fl oz/A (foliar application); PHI 7d, REI 12-48h, Group 29. Cabbage and Chinese cabbage ONLY. REI = 48h for handset irrigation, 12h for all other activites.
• fluopicolide (Presidio): 3.0 to 4.0 fl oz/A; PHI 2d, REI 12h, Group 43. Tank mix with a fungicide from a different group.
• fosetyl aluminum (Aliette WDG): 3.0 to 5.0 lb/A; PHI 3d, REI 12h, Group 33. Do not mix with copper fungicides. Lower rates of Aliette (2 to 3 lb) can be used when tank mixed with another fungicide labeled for downy mildew control.
• mancozeb plus copper hydroxide (ManKocide): 1.0 to 1.75 lb/A; PHI 7d, REI 48h, Groups M 03 & M 01. Broccoli and cabbage only.
• mandipropamid (Revus): 8.0 fl oz/A; PHI 1d, REI 4h, Group 40. A spreading/penetrating type adjuvant must be added.
• mefenoxam (Subdue MAXX): 25 to 50 pt/A; PHI 7d, REI 48h, Group 4. Do not apply foliar sprays without a labeled tank mix partner.
• mefenoxam plus chlorothalonil (Ridomil Gold Bravo): 1.5 pt/A; PHI 7d, REI 48h, Groups 4 and M 05. See label for plant-back restrictions and restrictions on certain crucifers.
• oxathiapiprolin and mandipropamid (Orondis Ultra): 5.5 to 8.0 fl.oz/A; PHI 1d, REI 4h, Groups 49 and 40. Begin foliar application prior to disease development. Use higher rate when disease is present. A spreading/penetrating adjuvant must be added.
• phosphorous acid  (Fosphite): 1.0 to 3.0 qt/100 gal; PHI 0d, REI 4h, Group 33. Do not apply to plants that are heat or moisture stressed. Do not apply directly to copper treated plants within 20-day interval to avoid plant injury.
• potassium bicarbonate (PB 133, AKA MilStop^OG): 2.5 to 5.0 lb/100 gal; PHI 0d, REI 1h, Group NC. See label for small volume application rates.
• Pseudomonas chlororaphis (Howler^OG): 2.5 to 7.5 lbs/A. PHI 0d, REI 4h, Group BM 02. Use preventatively.
• pyraclostrobin (Cabrio EG): 12.0 to 16.0 oz/A; PHI 0d, REI 12h, Group 11.
• Reynoutria sachalinensis extract (Regalia^OG): 1.0 to 4.0 qt/A ground application; PHI 0d, REI 4 h, Group P5. Apply to ensure thorough coverage. See label for specific application instructions.

Fusarium Yellows

This fungal pathogen is soil-borne and may also be seedborne. Plant resistant varieties. Prevent the movement of infested soil to clean fields. Provide adequate fertility; potassium deficiency increases disease severity.

Seed Decay and Damping-off

Buy treated seed. Do not use treated seed for food, feed or oil purposes.

• Bacillus amyloliquefaciens strain D747 (DoubleNickel^OG): 0.125 to 1.0 lb/A at planting; PHI 0d, REI 4h, Group 02. Suppression only.
• mefenoxam (Apron XL): 0.32 to 0.64 fl oz/lb seed; REI 48h, Group 4. For Pythium damping-off protection.
• Streptomyces griseoviridis strain K61 (MycoStop^OG): See label for rate information; REI 4h.
• thiram (Thiram 42-S): 8.0 fl oz/100 lb.; REI 24h, Group M 03.

Wire Stem, Crater rot, and Head rot (Rhizoctonia solani)

Diseases of brassica crops in this section caused by R. solani include wirestem and damping-off (seedlings), crater rot (root crops), and bottom or head rot (cabbage). Lesions caused by Rhizoctonia are brown to black and may be sunken. Rhizoctonia can be carried on the seeds of most brassica species and is ubiquitous in most soils, where it survives indefinitely. Start with certified, disease-free seed. Practice good sanitation in transplant production – successful sanitation in transplant production prevents further need for fungicide drenches. Use treated seed for direct seeding into field. Practices that encourage rapid germination and establishment limit disease development. Avoid planting transplants too deeply. Rotate crops. Do not plant susceptible crucifers in fields with undecomposed crop residues. No highly resistant varieties are available. Fungicide treatments in the field have limited effectiveness.

• PCNB (Blocker 4F): Rate varies depending upon application method - see label; REI 12h, Group 14. Note: pathogen referred to as Corticium solani on label.
• polyoxin D (OSO 5%SC): 6.5 to 13.0 fl oz/A; PHI 0d, REI 4h, Group 19.

Turnip Mosaic Virus

Turnip mosaic virus can infect most brassica crops but it is most commonly seen in Chinese cabbage and bok choy. It is spread by many species of aphids in a nonpersistent manner; therefore, insecticides are of little or no value in controlling its spread. This virus survives the winter in perennial weeds. Symptoms vary with host and include yellow and/or necrotic spots, mosiac, leaf deformity, and interveinal chlorosis. Environmental conditions also affect symptom expression. Partially resistant cultivars include 'Nabyeng', 'Kongng', 'Tip Top', and 'Ta Feng'. These cultivars may be intolerant of heat.

Insect Control

NOTES:  For the insecticides listed below, one product trade name and formulation is provided for each active ingredient (AI) as an example of rates, preharvest interval (PHI), restricted entry interval (REI), and special instructions. In many cases, there are other products available with the same AI. Please see Table 26 and Insecticides Alphabetical Listing by Trade Name for more information on these insecticides.

All tolerances for chlorpyrifos in food crops were revoked in 2022, therefore products containing chlorpyrifos (e.g. Lorsban) cannot be applied to any food crop and growers CAN NOT use up existing stock.

• The designation (Bee: L, M, or H) indicates a bee toxicity rating of low, moderate, or high. See the Protecting Honeybees and Native Pollinators section for more details.
• The symbol * indicates a product is a restricted use pesticide. See Pesticide Safety and Use for more details.
• The symbol ^OG   indicates a product is listed by the Organic Materials Review Institute (OMRI) as approved for use in organic production. See Organic Certification section for more details.

Cabbage Aphid (Brevicoryne brassicae)

Only crops and weeds in the brassica family are suitable hosts for cabbage aphid (CA).  Cabbage, cauliflower, broccoli and Brussels sprouts are most severely affected, but other crops may become infested. Aphids tend to be more of a problem in fall plantings. Adults, both winged and wingless, and nymphs are grayish green with a dark head and short, dark cornicles, but appear more grayish white because the body is covered with a fine, white, powdery secretion. In fall, eggs are laid on the underside of leaves of the same crops or weeds that were fed on during the summer, and survive the winter on brassica host plants. This differs from the life cycle of many aphid pests of vegetables, where eggs are laid and overwinter on alternate hosts outside the field. Eggs typically hatch in April. Nymphs feed and develop into reproductive females who produce live young without mating. Winged adults disperse with wind and infest new crops. There are multiple summer generations and potential for huge population growth, especially where long-season crops are infested early. CA prefers to feed on young leaves, flower buds or seed stalks in the upper part of the plant and also feeds in developing Brussels sprout buds. Dense colonies may develop. Feeding injury includes wrinkled and downward-curling leaves, yellow leaves, reduced growth, contamination with aphid honeydew, and contamination of the marketable parts of the plant with aphids. CA can also transmit cauliflower mosaic and cabbage ring spot virus, among other viruses; transmission is non-persistent, with virus particles passed to new plants by probing. Natural enemies can suppress cabbage aphid populations, but may not be able to prevent high densities that may occur in cool fall weather. Cultural controls include soil incorporation of crop residues immediately after harvest or, for overwintering brassicas, before eggs hatch in spring. Control brassica weeds in or near fields. Check transplants to be sure they are clean. Use reflective mulch to repel aphids. Use selective products when controlling other pests to conserve beneficials. If CA is a consistent problem, systemic insecticides used at planting or sidedress may eliminate early infestations. Scout weekly to determine % infested plants, starting before harvested portions of the plant form. Treat if >10% of the plants are infested with aphids, especially after heads or sprouts begin to form. Or select 10 leaves at 10 sites for 100 leaves per field, and treat if >20% have aphids. Coverage of all leaf surfaces, buds and new growth is key. Waiting until there are heavy outbreaks or until just before harvest makes it hard to prevent loss of marketable yield.

Green peach aphid (Myzus persicae) can also infest brassicas.  For more information, see green peach aphid in the Pepper section

• acephate (Orthene 97): 0.5 to 1 lb/A; PHI 14d, REI 24h, Bee: H, Group 1B. For green peach aphid. For Brussels sprouts and cauliflower only.
• acetamiprid (Assail 30SG): 2 to 4 oz/A; PHI 7d, REI 12h, Bee: H, Group 4A.
• afidopyropen (Versys): 1.5 fl oz/A; PHI 0d, REI 12 h, Bee: L, Group 9D.
• azadirachtin (Azatin O^OG): 4 to 16 oz/A foliar or drench, 4 to 16 oz/100 gal in greenhouses; PHI 0d, REI 4h, Bee: L, Group UN. When using lower rates, combine with adjuvant for improved spray coverage and translaminar uptake.
• Beauveria bassiana (Mycotrol ESO^OG): 8 to 32 oz/A; PHI 0d, REI 4h, Bee: L, Group UN. Treat when populations are low and thoroughly cover foliage. Takes 7 to 10 days after the first spray to see control. Repeat applications may be needed.
• bifenthrin (Brigade* 2EC): 2.1 to 6.4 oz/A; PHI 7d, REI 12h, Bee: H, Group 3A.
• Burkholderia spp. strain A396 (Venerate XC^OG): 2 to 4 qt/A; PHI 0d, REI 4h, Bee: M, Group UN. Suppression only.
• Chromobacterium subtsugae strain PRAA4-1 (Grandevo^OG): 2 to 3 lb/A; PHI 0d, REI 4h, Bee: M, Group UN.
• cyantraniliprole (Exirel): 13.5 to 20.5 oz/A; PHI 1d, REI 12h, Bee: H, Group 28.
• cyantraniliprole (Verimark):  6.75 to 13.5 oz/A; PHI 0d, REI 4h, Bee: H, Group 28. For soil applications at planting.
• dimethoate (Dimethoate 4EC): 8 to 16 oz/A for broccoli and cauliflower, 8 oz/A for kale and mustard, 16 oz/A Brussels sprouts; PHI 7d broccoli and cauliflower, 14d kale and mustard, 0d Brussels sprouts, REI 48h, Bee: H, Group 1B. Broccoli, cauliflower, kale, mustard, Brussels sprouts only.
• dinotefuran (Safari 20SG): 0.16 to 0.32 oz/1,000 sq ft; 3.5 to 7 oz/100 gal; 7 to 14 oz/A; REI 12h, Bee: H, Group 4. Broccoli, Brussels sprouts, cabbage, cauliflower and kohlrabi transplants only while in greenhouse. Not for field use.
• dinotefuran (Venom): 1 to 4 oz/A for foliar applications or 5 to 7.5 oz/A for soil applications to head and stem Brassicas. 2 to 3 oz/A for foliar application only to leafy Brassicas; PHI 1d foliar, 21d soil, REI 12h, Bee: H, Group 4A. Soil application may be as a band during bedding, in-furrow at seeding, transplant or post-seeding drench, sidedress or through drip. For head and stem Brassicas only. Suppression only.
• fenpropathrin (Danitol* 2.4EC): 10.66 to 16 oz/A; PHI 7d, REI 24h, Bee: H, Group 3. May be combined with Belay insecticide (see label for rates and 21d PHI). Do not apply during bloom or if bees are actively foraging. For head and stem brassicas only.
• flonicamid (Beleaf 50SG): 2 to 2.8 oz/A; PHI 0d, REI 12h, Bee: L, Group 9C.
• flupyradifurone (Sivanto): 7 to 14 oz/A foliar, 21 to 28 oz/A soil; PHI 1d foliar, 21d soil, REI 4h, Bee: L, Group 4D.
• imidacloprid (Admire Pro): 4.4 to 10.5 oz/A soil; 1.3 oz/A foliar; PHI 21d soil, 7d foliar, REI 12h, Bee: H, Group 4A.
• insecticidal soap (M-Pede^OG): 1.25 to 2.5 oz/gal water; PHI 0d, REI 12h, Bee: L. Spray to wet all infested plant surfaces. May need to make repeated applications. For enhanced and residual control, apply with companion labeled insecticide.
• lambda-cyhalothrin (Warrior* II): 1.28 to 1.92 oz/A; PHI 1d, REI 24h, Bee: H, Group 3A. For head and stem Brassicas only. Suppression only.
• malathion (Malathion 57 EC): 1 to 2 pt/A for broccoli, Brussels sprouts, cauliflower, cabbage, kohlrabi; 1 to 1.6 pt/A for kale and mustard greens; 1.5 to 1.6 pt/A for collards; PHI 2d broccoli, Brussels sprouts, cauliflower; 7d cabbage, kale, collards, kohlrabi, mustard greens, REI 48h broccoli, Brussels sprouts, cabbage, cauliflower; 24h kohlrabi; 12h collards, kale, mustard greens, Bee: H, Group 1B.
• petroleum oil (Suffoil X^OG): 1 to 2 gal/100 gal water; PHI 0d, REI 4h, Bee: L. Apply as needed.
• pymetrozine (Fulfill): 2.75 oz/A; PHI 7d, REI 12h, Bee: L, Group 9A. Selective control of aphids including cabbage aphid. Translaminar.
• pyrethrin (PyGanic EC5.0^OG): 4.5 to 17 oz/A; 0.25 to 0.50 oz/gal, 3 gal/1000 sq ft in greenhouse for backpack sprayers; PHI 0d, REI 12h, Bee: M, Group 3A.
• sodium tetraborohydrate decahydrate (Prev-AM): 100 oz/100 gal; REI 12h, Bee: L, Group 25. Do not apply in midday sun or mix with copper, sulfur or oils.
• spirotetramat (Movento): 4 to 5 oz/A; PHI 1d, REI 24h, Bee: M, Group 23. Must be tank-mixed with a spray adjuvant with spreading and penetrating properties to maximize leaf uptake and sytemicity; don't use sticker adjuvants. Controls immature stages; may also reduce adult fertility.
• sulfoxaflor (Closer SC): 1.5 to 2 oz/A; PHI 3d, REI 12h, Bee: H, Group 4C.
• thiamethoxam (Actara): 1.5 to 3 oz/A; PHI 7d leafy Brassica greens, 0d head and stem brassicas, REI 12h, Bee: H, Group 4A.
• thiamethoxam (Platinum): 5 to 11 oz/A; PHI 30d, REI 12h, Bee: H, Group 4A. Systemic insecticide used as an in-furrow, banded, drench, or drip irrigation application to the seed/seedling root zone during or after planting/transplanting operations or shanked into root zone after transplanting or establishment.
• tolfenpyrad (Torac): 17 to 21 fl oz/A; PHI 1d, REI 12h, Bee: H, Group 21A.

Cabbage Looper (Trichoplusia ni), Diamondback Moth (Plutella xylostella) and Imported Cabbageworm (Pieris rapae)

Diamondback moth (DBM) and imported cabbageworm (ICW) are pests throughout the growing season, while cabbage looper (CL) generally does not become a pest until mid- to late-season.

Imported cabbageworm (ICW) is the offspring of the cabbage butterfly, a daytime flyer often visible in brassica fields. Wings are white, and the forewing has a dark border and 1-2 round black spots. Eggs, laid singly on leaves, are about 0.125 in. long, light green or yellow, and slightly elongated, standing upright. Imported cabbageworm caterpillars are gray-green with a thin yellow line down the back, slightly fuzzy, reach 1.25 in. long, and are sluggish when touched. Feeding and resting occur on the underside of leaves, and larvae feed more heavily in the center or head of cabbage or broccoli. Damage includes round or ragged feeding holes and deposits of wet, green or brownish frass. The overwintering stage is the chrysalis (pupa), which is green or brown, smooth, with 3 pointed ridges on its back. There are 3-4 generations per year with adults first appearing in May.

Cabbage looper (CL) does not overwinter in New England but arrives in migratory flights from farther south. Generally, numbers are not significant until late July or August. Adult moths are mottled gray-brown, 0.75 in. long, with a distinct, round, silver-white mark on the wing. Bucket-type pheromone traps can be used to monitor moth flight. Eggs are globe-shaped, light green or yellow, and laid underneath the foliage. Caterpillars are light green, with wavy, white or light yellow lines down the back and sides, reaching 1.5-2 in. when full grown. Cabbage loopers of any size move like inchworms by raising the middle of their body in a characteristic "loop" shape. Feeding damage from older larvae consists of ragged, large holes in foliage, on both frame leaves and heads.

Diamondback moth (DBM) adults are small (<0.5 in.), light brown with a yellow diamond-shaped marking, and rest with their wings folded together like a tent. Adult moths are active at dusk and during the night. Caterpillars reach a length of 3/4 in., are light green, and are segmented and pointed at both ends. When disturbed they wiggle vigorously and may drop off the plant on a string of silk. Feeding causes small, round holes and tends to be spread across the foliage rather than concentrated in the head.

Incorporate crop residues shortly after harvest to reduce movement to successive plantings and reduce overwintering populations. Populations are suppressed by a wide range of natural enemies and there are several selective materials that control caterpillars and have minimal non-target effects (e.g. Xentari, Dipel, Coragen, Intrepid). Parasitic wasps that attack caterpillars include Cotesia rubecula on ICW and Diadegma insulare on DBM; their small white cocoons may be found on leaves.

Scout fields by checking leaves (top and bottom) on 25 plants across the field. In the Northeast, there is generally no need to treat young plants unless weather conditions delay plant development and at least 35% of them are infested with any of these pests. Treat plants between the start of heading and harvest if 20% or more of the plants are infested. The most critical time to scout and apply chemical controls is just prior to head formation. Use a 10-15% threshold throughout the season for kale, collards, mustard, and other leafy greens.

Do not use less than 50 gal spray material/A; higher volumes provide better coverage. Better coverage of lower leaf surfaces can be achieved by using drop nozzles. Use a spreader-sticker. Use selective materials to spare beneficials that help control aphids and caterpillars. DBM has become resistant to many synthetic and microbial insecticides.  Even if you are getting excellent control of this pest with the materials presently being used, you should alternate between effective materials to retard development of resistance. Newer materials and the aizawai strain of Bacillus thuringiensis will usually provide better control of resistant DBM than older products. Use transplants grown in New England to avoid importing DBM that have already developed resistance to one or more classes of insecticides.

• acephate (Orthene 97): 1 lb/A; PHI 14d, REI 24h, Bee: H, Group 1B. For Brussels sprouts and cauliflower only. DBM has developed resistance in some areas. 
• acetamiprid (Assail 30SG): 4 oz/A; PHI 7d, REI 12h, Bee: H, Group 4A. For suppression of DBM only.
• alpha-cypermethrin (Fastac* EC): 2.2 to 3.8 oz/A DBM and ICW, 3.2 to 3.8 oz/A looper; PHI 1d, REI 12h, Bee: H, Group 3A.
• azadirachtin (Azatin O^OG): 4 to 16 oz/A foliar or drench, 4 to 16 oz/100 gal in greenhouses; PHI 0d, REI 4h, Bee: L, Group UN. When using lower rates, combine with adjuvant for improved spray coverage and translaminar uptake.
• azadirachtin & pyrethrins (Azera^OG): 16 to 56 oz/A foliar, drench, and greenhouse applications; PHI 0d, REI 12h, Bee: M, Groups un & 3A.
• Bacillus thuringiensis aizawai (XenTari^OG): 0.5 to 1.5 lb/A; PHI 0d, REI 4h, Bee: L, Group 11. Must be ingested; apply in evening or early morning, before larvae are actively feeding. Adherence and weather-fastness will improve with use of an approved spreader-sticker. Use high rate at cool temperatures. Particularly effective against DBM. For resistance management, may be rotated with Bt kurstaki products (Dipel).
• Bacillus thuringiensis kurstaki (Dipel DF^OG): 0.5 to 2 lb/A DBM & ICW, 0.5 to 1 lb/A looper; PHI 0d, REI 4h, Bee: L, Group 11. Must be ingested; apply in evening or early morning, before larvae are actively feeding. Adherence and weather-fastness will improve with use of an approved spreader-sticker. Use high rate at cool temperatures. Particularly effective against DBM. For resistance management, may be rotated with Bt aizawai products (XenTari).
• Beauveria bassiana (Mycotrol ESO): 16 to 32 oz/A; PHI 0d, REI 4h, Bee: L, Group UN. Use high rate for CL. May be used alone or tank mixed with Bacillus thuringiensis products. Takes 7 to 10 days after application to see control.
• beta-cyfluthrin (Baythroid* XL): 1.6 to 2.4 oz/A for CL and ICW, 2.4 to 3.2 oz/A for DBM; PHI 0d, REI 12h, Bee: H, Group 3A.
• bifenthrin (Brigade* 2EC): 2.1 to 6.4 oz/A; PHI 7d, REI 12h, Bee: H, Group 3A.
• Burkholderia spp. strain A396 (Venerate XC^OG): 1 to 4 qt/A; PHI 0d, REI 4h, Bee: M, Group UN.
• carbaryl (Sevin XLR Plus): 1 to 2 qt/A; PHI 3d broccoli, Brussels sprouts, cabbage, cauliflower and kohlrabi, 14d Chinese cabbage, collards, kale and mustard greens, REI 12h, Bee: H, Group 1A. DBM and ICW only.
• chlorantraniliprole (Coragen): 3.5 to 7.5 oz/A; PHI 3d, REI 4h, Bee: L, Group 28. May be applied to soil at planting, through drip chemigation and as a foliar spray. Do not apply more than twice to any generation of DBM.
• Chromobacterium subtsugae strain PRAA4-1 (Grandevo^OG): 1 to 3 lb/A; PHI 0d, REI 4h, Bee: M, Group UN.
• cryolite (Prokil Cryolite): 8 to 16 lb/A; PHI 7d, REI 12h, Bee: L, Group UN. Broccoli, Brussels sprouts and cauliflower only. 
• cyantraniliprole (Exirel): 10 to 17 oz/A for CL, 7 to 13.5 oz/A for ICW and DBM; PHI 1d, REI 12h, Bee: H, Group 28. For DBM resistance management, do not apply Exirel more than twice within any 30-day "treatment window".
• cyantraniliprole (Verimark):  6.75 to 10 oz/A for CL, 5 to 10 oz/A for DBM and ICW; PHI 1d chemigation, REI 4h, Bee: H, Group 28. For soil applications at planting and drip chemigation.
• cyclaniliprole (Harvanta): 10.9 to 16.4 fl oz/A; PHI 1d, REI 4 h, Bee: H, Group 28. See label for DBM resistance management.
• emamectin benzoate (Proclaim*): 2.4 to 4.8 oz/A for DBM and ICW, 3.2 to 4.8 oz/A for CL; PHI 7d head and stem, 14d leafy brassicas, REI 12h, Bee: H, Group 6. Rotate to another product after 2 applications.
• esfenvalerate (Asana* XL): 5.8 to 9.6 oz/A for most species, 2.9 to 5.8 oz/A for ICW on broccoli, cabbage, cauliflower, and Chinese cabbage; PHI 3d broccoli, cabbage, cauliflower, Chinese cabbage, kohlrabi, 7d collards and mustard greens, REI 12h, Bee: H, Group 3A. Use high rate for mustard greens. Not for DBM. Not for ICW on kohlrabi.
• fenpropathrin (Danitol* 2.4EC): 10.66 to 16 oz/A; PHI 7d, REI 24h, Bee: H, Group 3. For head and stem brassicas only. May be combined with DiPel DF on head and stem brassicas only - see label for rates.
• gamma-cyhalothrin (Declare*): 0.77 to 1.28 oz/A for looper and ICW, 1.02 to 1.54 oz/A DBM; PHI 1d, REI 24h, Bee: H, Group 3A. Head and stem Brassicas only.
• indoxacarb (Avaunt): 2.5 to 3.5 oz/A; PHI 3d, REI 12h, Bee: H, Group 22. Use high rate for DBM. Add a wetting agent to improve spray coverage.
• lambda-cyhalothrin (Warrior* II): 0.96 to 1.6 oz/A for CL and ICW, 1.28 to 1.92 oz/A for DBM; PHI 1d, REI 24h, Bee: H, Group 3A. For head and stem Brassicas.
• malathion (Malathion 57 EC): 1 to 2 pt/A for broccoli, Brussels sprouts, cauliflower, cabbage, kohlrabi, 1 to 1.6 pt/A for kale and mustard greens; 1.6 pt/A for collards; PHI 2d broccoli, Brussels sprouts, cauliflower, 7d cabbage, kale, collards, kohlrabi, mustard greens, REI 48h broccoli, Brussels sprouts, cabbage, cauliflower; 24h kohlrabi; 12h collards, kale, mustard greens, Bee: H, Group 1B. Not for DBM except on collards.
• methomyl (Lannate* LV): 1.5 to 3 pt/A for CL and DBM, 0.75 to 3 pt/A for ICW on broccoli, cabbage, cauliflower, 1.5 to 3 pt/A for ICW on Brussels sprouts, collards, kale, mustard greens; PHI 1d cabbage, 3d broccoli, Brussels sprouts, cauliflower, 10d Chinese cabbage, collards, kale, mustard greens, REI 48h, Bee: H, Group 1A. Not for ICW or DBM on Chinese cabbage. Add wetting agent to improve coverage. 
• methoxyfenozide (Intrepid 2F): 4 to 10 oz/A for ICW and CL; 12 to 16 oz/A for DBM; PHI 1d, REI 4h, Bee: L, Group 18. Suppression only for DBM. Use lower rates when plants are small and infestations are light for CL and ICW.
• novaluron (Rimon 0.83EC): 6 to 12 oz/A; PHI 7d, REI 12h, Bee: L, Group 16B. Not labeled for collards, kale. Most effective on 1st and 2nd instars.
• permethrin (Pounce* 25WP): 3.2 to 6.4 oz/A for Brussels sprouts, cauliflower, cavalo broccolo and kohlrabi, 3.2 to 12.8 oz/A for broccoli, Chinese broccoli, cabbage and Chinese cabbage; PHI 1d, REI 12h, Bee: H, Group 3A. Not for other Brassica crops.
• pyrethrin (PyGanic EC5.0^OG): 4.5 to 17 oz/A; 0.25 to 0.50 oz/gal, 3 gal/1000 sq ft in greenhouse for backpack sprayers; PHI 0d, REI 12h, Bee: M, Group 3A.
• sodium tetraborohydrate decahydrate (Prev-AM): 50 oz/100 gal; REI 12h, Bee: L, Group 25. Do not apply in midday sun or mix with copper, sulfur or oils. Cabbage looper only. 
• spinetoram (Radiant SC): 5 to 10 oz/A; PHI 1d, REI 4h, Bee: M, Group 5. Efficacy improves with the addition of an adjuvant.
• spinosad (Entrust SC^OG): 3 to 6 oz/A looper & ICW, 1.5 to 4 oz/A DBM; PHI 1d, REI 4h, Bee: M, Group 5. See label for resistance management restrictions for DBM.
• tebufenozide (Confirm 2F): 6 to 8 oz/A; PHI 7d, REI 4h, Bee: L, Group 18. Use low rate for early season applications to young, small plants. Use of an adjuvant is recommended. Not for DBM.
• tolfenpyrad (Torac): 17 to 21 fl oz/A; PHI 1 d, REI 12h, Bee: H, Group 21A. Not for CL. 
• zeta-cypermethrin (Mustang*): 2.24 to 4 oz/A for DBM, ICW, 3.2 to 4 for CL; PHI 1d, REI 12h, Bee: H, Group 3A.

Cabbage Maggot (Delia radicum)

Cabbage root maggot is a pest of all types of brassicas, but is particularly damaging in cabbage, broccoli, Chinese cabbage, radish, turnips, and rutabaga. The first flight in April and May damages early spring brassicas, and the third flight from mid-August into September primarily injures fall root crops. Flies overwinter as pupae near roots of fall brassica crops and weeds. Adult flies become active at about 288 growing degrees days (GDD, base temperature 40°F), which occurs 1-2 weeks after forsythia starts to bloom and when yellow rocket (winter cress, Barbarea vulgaris) blooms. Fifty percent emergence (peak flight) occurs at about 450 GDD (base 40°F). Adult flies are delicate, hump-backed, gray-brown flies with long legs, about 5-7 mm long. Small (1.1mm), white, bullet-shaped eggs are laid singly or in clumps in the top 1-3 inches of soil, near the stem. Wet areas with heavy or rich soil are attractive for egg-laying. Maggots are white with black mouth hooks, feed on roots, and grow to 8 mm. The oval, brown pupae are found close to the roots. There are 2 to 3 generations per year in New England. Root damage causes plants to wilt, turn yellow or purple, become stunted or delayed, or die. Early infestation and large pest populations increase plant losses. Eggs are killed by exposure to soil temperatures above 95°F for several days in a row, especially in dry soil. Often these conditions occur in late May or early June.

Incorporate and disk brassica crop residues after harvest to expose and kill pupae, especially in the fall. Rotate spring crops to fields that were not planted with brassicas the previous fall. Avoid spring applications of manure or compost, which increase attractiveness of the field for egg-laying.  Avoid wet fields or sections of the field. Protect spring crops with spunbonded row covers, and use covers only on rotated fields, or else the flies will emerge under the covers.  Place covers over the crop at the time of seeding or transplanting and seal the edges with soil. Time your seeding or transplanting to avoid exposing young plants to peak flight periods; delay spring crops until after peak flight and when soils warm up. 

Most labeled materials are labeled only for use pre-plant, at the time of planting or seeding—either in the seed furrow or as a transplant drench—or immediately after setting transplants. Use pre- or at-plant treatments only if damaging populations are expected, such as in fields with high organic matter or a history of infestations. Scout transplant trays before setting out plants in the field. Treat transplants if eggs are found, either in the tray, in transplant water, or as a post-plant drench, as labels allow. A pencil is a good tool to gently stir the soil at the base of the plant and look for eggs. Yellow sticky cards placed near brassicas capture adult flies, and along with GDD, are a good indicator of the onset of adult flight. Scout for eggs—in transplant trays and the field—as soon as flies are active. In the field, finding an average of 1egg per plant can indicate a damaging population. Again, control options are limited once plants are in the field, but scouting to understand infestation levels can help inform management decisions in future plantings. Resistance to organophosphate (group 1B) insecticides has been documented; rotate among chemical classes where possible to retard development of resistance. 

• bifenthrin (Capture LFR): 3.4 to 6.8 oz/A; REI 12h, Bee: H, Group 3. Apply as a 5 to 7-inch T-band over the open seed furrow, or in-furrow with the seed. Head and stem brassicas only. 
• chlorantraniliprole (Coragen): 3.5 to 7.5 oz/A; PHI 3d, REI 4h, Bee: L, Group 28. May only be applied as transplant water treatment to soil at planting. For suppression only.
• cyantraniliprole (Verimark):  10 to 13.5  oz/A; PHI 0d, REI 4h, Bee: H, Group 28. For soil applications at planting.
• diazinon (Diazinon* AG500): For pre-plant broadcast and incorporation applications: 2 to 3 qt/A; For transplant water drench applications: 4 to 8 oz/50 gal water; PHI 7d, REI 4 days, Bee: H, Group 1B. Broccoli, Brussels sprouts, cabbage, cauliflower only. Transplant water treatments may result in stand reduction due to plant stress at time of transplanting.
• spinetoram (Radiant SC): 5 to 10 oz/A; PHI 1d, REI 4h, Bee: M, Group 5. Suppression only. For direct seeded crops, apply directly to base of plants and adjacent soil when crop has developed to the two true leaf stage, and make second application 2-3 weeks later. For transplanted crops, apply immediately after transplanting and make second application 2-3 weeks later. A third application may be needed under high cabbage root maggot pest pressure conditions, such as when there is a large amount of debris from a previous brassica crop or when adjacent brassica fields are being harvested. For optimum control, direct the spray in a narrow band at the base of the plants. Do not make more than three applications of Group 5 insecticides (spinetoram and spinosad) per crop cycle for cabbgage root maggot suppression. For brassica leafy vegetables only (e.g., broccoli, Brussels sprouts, cabbage, kale). Not for brassica roots (e.g., radish, turnip). 
• spinosad (Entrust SC^OG): 5 to 10 oz/A; PHI 1d, REI 4h, Bee: M, Group 5. Suppression only. For direct seeded crops, apply directly to base of plants and adjacent soil when crop has developed to the two true leaf stage, and make second application 2-3 weeks later. For transplanted crops, apply immediately after transplanting and make second application 2-3 weeks later. A third application may be needed under high cabbage root maggot pest pressure conditions, such as when there is a large amount of debris from a previous brassica crop or when adjacent brassica fields are being harvested. For optimum control, direct the spray in a narrow band at the base of the plants. Do not make more than three applications of Group 5 insecticides (spinetoram and spinosad) per crop cycle for cabbgage root maggot suppression. For brassica leafy vegetables only (e.g., broccoli, Brussels sprouts, cabbage, kale). Not for brassica roots (e.g., radish, turnip). 
• tolfenpyrad (Torac): 21 fl oz/A; PHI 1d, REI 12h, Bee: H, Group 21A.

Cabbage Whitefly (Aleyrodes proletella)

An emerging pest in the Northeast United States, cabbage whitefly originates from Europe and is a pest in many areas of the world. Adults are small (1.5 mm) with white wings, and can be distinguished from greenhouse and sweet potato whitefly by two gray blotches on each forewing. Eggs are laid in a half-moon or circular pattern on the undersides of leaves. Immature stages are flat and scale-like. Both adults and nymphs feed on plant sap. Large populations will reduce plant vigor and quality, and adults and nymphs deposit honeydew on leaf surfaces on which sooty mold grows. Cabbage whitefly feeds and reproduces on brassicas, as well as other crops and weeds such as alfalfa, fava bean and dandelion. Preferred hosts are kale and Brussels sprouts.  

• beta-cyfluthrin (Baythroid* XL): 3.2 oz/A; PHI 7d, REI 12h, Bee: H, Group 3A. For suppression of adults only.
• bifenthrin (Brigade* 2EC): 2.1 to 6.4 oz/A; PHI 7d, REI 12h, Bee: H, Group 3A.
• Chromobacterium subtsugae strain PRAA4-1 (Grandevo^OG): 2 to 3 lb/A; PHI 0d, REI 4h, Bee: M, Group UN.
• chlothianidin (Belay): 3 to 4 fl oz/A; PHI 7d, REI 12h, Bee: H, Group 4A. Suppression only. Do not use on crops grown for seed. Must not be applied during bloom or when bees are foraging. 
• cyantraniliprole (Exirel): 13.5 to 20.5 oz/A; PHI 1d, REI 12h, Bee: H, Group 28.
• cyantraniliprole (Verimark): 6.75 to 13.5 oz/A at planting, 6.75 to 10 oz/A chemigation; PHI 1d, REI 4h, Bee: H, Group 28. For soil applications at planting, drip chemigation, or soil injection. Allow 1-3 days for material to be translocated into aerial portions of the plant. When populations are high, use a foliar control during this period.
• dinotefuran (Venom): 1 to 4 oz/A foliar or 5 to 7.5 oz/A soil for heading brassicas, 2 to 3 oz/acre leafy; PHI 1d foliar, PHI 21d soil, REI 12h, Bee: H, Group 4A. Soil application may be as a band during bedding, in-furrow at seeding, transplant or post-seeding drench, sidedress or through drip.
• flupyradifurone (Sivanto): 10.5 to 14 oz/A foliar, 21 to 28 oz/A soil; PHI 1d foliar, 45d soil, REI 4h, Bee: L, Group 4D.
• gamma-cyhalothrin (Declare*): 1.02 to 1.54 oz/A; PHI 1d, REI 24h, Bee: H, Group 3A. Suppression only. Head and stem brassicas only. 
• imidacloprid (Admire Pro): 4.4 to 10.5 oz/A soil, 1.3 oz/A foliar, 0.44 oz/10,000 plants on seedling transplants in greenhouse; PHI 21d soil, PHI 7d foliar, REI 12h, Bee: H, Group 4A. Planthouse applications only provide short-term protection; an additional field application must be made within 2 weeks following transplanting to provide continuous protection.
• insecticidal soap (M-Pede^OG): 1.25 to 2.5 oz/gal water; PHI 0d, REI 12h, Bee: L. Spray to wet all infested plant surfaces. May need to make repeated applications. For enhanced and residual control, apply with a companion labeled insecticide.
• lambda-cyhalothrin (Warrior* II): 1.28 to 1.92 oz/A; PHI 5d, REI 24h, Bee: H, Group 3A. Suppression only. Head and stem brassicas only.
• petroleum oil (Suffoil X^OG): 1 to 2 gal/100 gal water; PHI 0d, REI 4h, Bee: L. Apply as needed.
• pymetrozine (Fulfill): 2.75 oz/A; PHI 7d, REI 12h, Bee: L, Group 9A. Suppression only. Apply when whiteflies first appear.
• pyrethrin (PyGanic EC5.0^OG): 4.5 to 17 oz/A; 0.25 to 0.50 oz/gal, 3 gal/1000 sq ft in greenhouse for backpack sprayers; PHI 0d, REI 12h, Bee:M, Group 3A.
• pyriproxyfen (Knack): 8 to 10 fl oz/A; PHI 7d, REI 12h, Bee: L, Group 7C. Insect growth regulator, only effective on immature stages. Higher water volumes may provide improved control. 
• spiromesifen (Oberon 2SC): 7 to 8.5 oz/A; PHI 7d, REI 12h, Bee: M, Group 23. Most effective on egg and immature stages. Complete coverage is necessary. An adjuvant may be used to improve coverage and control. 
• thiamethoxam (Actara): 3.0 to 5.5 oz/A; PHI 7d leafy brassica greens, 0d head and stem brassicas, REI 12h, Bee: H, Group 4A.
• thiamethoxam (Platinum): 5 to 11 oz/A; PHI 30d, REI 12h, Bee: H, Group 4A. Systemic insecticide used in an in-furrow, banded, drench, or drip irrigation application to the seedling root zone during or after transplanting operations or shanked into root zone after transplanting or establishment.

Cross-striped Cabbageworm (Evergestis rimosalis)

Formerly restricted to areas south of New England, this insect is now a significant pest of brassicas in CT, RI and MA. It has 2 to 3 generations per year and is most abundant on late-season plantings. Unlike the other major caterpillar pests on brassicas, the cross-striped cabbageworm (CSC) lays its eggs in batches (3-25) rather than singly, so caterpillars emerge in clusters. Egg batches are yellow, flattened, overlapping like fish scales, and attached to the lower leaf surfaces. Larvae grow to 3/4 in. long in 2-3 weeks. The caterpillars are light bluish-grey on top and green underneath, with numerous black bands across their backs and a yellow stripe down each side. Pupation takes place in soil, near the surface. Caterpillars produce small holes in leaves until only veins remain, or target terminal buds and sprouts, or may burrow into heads. Plants with larvae present are often completely skeletonized, while adjacent plants may be left undamaged. Plow under debris after harvest and control wild mustard and Shepherd's purse to help reduce pest populations. Scout weekly for caterpillars and damage. Spray if 5% of the plants are infested with CSC. Use selective insecticides to preserve parasitic wasps.

• azadirachtin & pyrethrins (Azera^OG): 16 to 56 oz/A foliar, drench, and greenhouse applications; PHI 0d, REI 12h, Bee: M, Groups UN & 3A.
• Bacillus thuringiensis aizawai (XenTari^OG): 0.5 to 1.5 lb/A; PHI 0d, REI 4h, Bee: L, Group 11. Must be ingested; apply in evening or early morning, before larvae are actively feeding. Adherence and weather-fastness will improve with use of an approved spreader-sticker. Use high rate at cool temperatures. For resistance management, may be rotated with Bt kurstaki products (Dipel).
• Bacillus thuringiensis kurstaki (Dipel DF^OG): 0.5 to 2 lb/A; PHI 0d, REI 4h, Bee: L, Group 11. Must be ingested; apply in evening or early morning, before larvae are actively feeding. Adherence and weather-fastness will improve with use of an approved spreader-sticker. Use high rate at cool temperatures. For resistance management, may be rotated with Bt aizawai products (XenTari).
• chlorantraniliprole (Coragen): 3.5 to 7.5 oz/A; PHI 3d, REI 4h, Bee: L, Group 28. May be applied to soil at planting, through drip chemigation and as a foliar spray.
• Chromobacterium subtsugae strain PRAA4-1 (Grandevo ^OG): 1 to 3 lb/A; PHI 0d, REI 4h, Bee: M, Group UN.
• cyclaniliprole (Harvanta): 10.9 to 16.4 fl oz/A; PHI 1d, REI 4 h, Bee: H, Group 28.
• emamectin benzoate (Proclaim*): 2.4 to 4.8 oz/A; PHI 7d heading and stem, 14d leafy brassicas and turnip greens, REI 12h, Bee: H, Group 6. Rotate to another product after 2 applications.
• fenpropathrin (Danitol* 2.4EC): 10.66 to 16 oz/A; PHI 7d, REI 24, Bee: H, Group 3. For head and stem brassicas only. May be combined at with Dipel DF for control of other caterpillars-see label for rates.
• indoxacarb (Avaunt): 2.5 to 3.5 oz/A; PHI 3d, REI 12h, Bee: H, Group 22. Add a wetting agent to improve spray coverage.
• methoxyfenozide (Intrepid 2F): 8 to 10 oz/A; PHI 1d, REI 4h, Bee: L, Group 18.
• pyrethrin (PyGanic EC5.0^OG): 4.5 to 17 oz/A; 0.25 to 0.50 oz/gal, 3 gal/1000 sq ft in greenhouse for backpack sprayers; PHI 0d, REI 12h, Bee: M, Group 3A.
• tebufenozide (Confirm 2F): 6 to 8 oz/A; PHI 7d, REI 4h, Bee: L, Group 18. Use low rate for early season applications to young, small plants. Use of an adjuvant is recommended.

Cutworm

See cutworms in the Pepper and Outdoor Tomato sections for more information on the black and variegated cutworms.

• alpha-cypermethrin (Fastac* EC): 2.2 to 3.8 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.
• Bacillus thuringiensis aizawai (XenTari^OG): 0.5 to 1.5 lb/A; PHI 0d, REI 4h, Bee: L, Group 11. Must be ingested; apply in evening or early morning, before larvae are actively feeding. Adherence and weather-fastness will improve with use of an approved spreader-sticker. Use high rate at cool temperatures. For resistance management, may be rotated with Bt kurstaki products (Dipel).
• Bacillus thuringiensis kurstaki (Dipel DF^OG): 0.5 to 2 lb/A; PHI 0d, REI 4h, Bee: L, Group 11. Must be ingested; apply in evening or early morning, before larvae are actively feeding. Adherence and weather-fastness will improve with use of an approved spreader-sticker. Use high rate at cool temperatures. For resistance management, may be rotated with Bt aizawai products (XenTari).
• beta-cyfluthrin (Baythroid* XL): 0.8 to 1.6 oz/A; PHI 0d, REI 12h, Bee: H, Group 3A.
• bifenthrin (Brigade* 2EC): 2.1 to 6.4 oz/A; PHI 7d, REI 12h, Bee: H, Group 3A.
• carbaryl (10% Sevin Granules): 20 lb/A; PHI 3d broccoli, Brussels sprouts, cabbage, cauliflower and kohlrabi, 14d Chinese cabbage, collards, kale, mustard greens, REI 12h, Bee: H, Group 1A. For broadcast treatment only. Use within 30 days of crop emergence or transplanting.
• Chromobacterium subtsugae strain PRAA4-1 (Grandevo^OG): 1 to 3 lb/A; PHI 0d, REI 4h, Bee: M, Group UN.
• cryolite (Prokil Cryolite): 8 to 16 lb/A; PHI 7d, REI 12h, Bee:L, Group UN. Broccoli, Brussels sprouts and cauliflower only. 
• diazinon (Diazinon* AG500): 2 to 4 qt/A broadcast and incorporate before planting; REI 24h, Bee: H, Group 1B. For broccoli, Brussels sprouts, cabbage, collards, kale, mustard greens and cauliflower.
• esfenvalerate (Asana*XL): 5.8 to 9.6 oz/A; PHI 3d, PHI 7d collards, REI 12h, Bee: H, Group 3A. For broccoli, cabbage, cauliflower, Chinese cabbage, collards only.
• fenpropathrin (Danitol* 2.4EC): 10.66 to 16 oz/A; PHI 7d, REI 24h, Bee: H, Group 3. Head and stem brassicas only. 
• gamma-cyhalothrin (Declare*): 0.77 to 1.28 oz/A; PHI 1d, REI 24h, Bee: H, Group 3A. Head and stem Brassicas only.
• lambda-cyhalothrin (Warrior* II): 0.96 to 1.6 oz/A; PHI 1d, REI 24h, Bee: H, Group 3A. Head and stem Brassicas only.
• methomyl (Lannate* LV): 1.5 pt/A; PHI 1d cabbage, 3d Brussels sprouts and cauliflower, 10d collards, REI 48h, Bee: H, Group 1A. For variegated cutworm only.
• methoxyfenozide (Intrepid 2F): 4 to 10 oz/A; PHI 1d, REI 4h, Bee: L, Group 18. Suppression only.
• permethrin (Pounce* 25WP): 6.4 to 12.8 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A. Cabbage and Chinese cabbage only.
• spinosad (Seduce^OG): 20 to 44 lb/A or 0.5 to1 lb/1000 sq ft; PHI 1d, REI 4h, Bee: M, Group 5. Spread bait on soil around plants.
• zeta-cypermethrin (Mustang*): 2.24 to 4 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.

Flea Beetles (Phyllotreta cruciferae and P. striolata)

In New England, two species are found on brassicas: the crucifer flea beetle (Phyllotreta cruciferae), which is uniformly black and shiny, about 2 mm in length; and the striped flea beetle (P. striolata), which is black with 2 yellow stripes on its back. These two species feed only on brassicas, and attack all types of brassica crops and weeds.  Populations have increased over the past twenty-five years, so that on many farms flea beetle is a key pest of brassicas. Adult beetles overwinter outside cropped fields, in the soil surface and decaying plant residue of shrubby or woody borders. They search out host crops from early May into June and feed on leaves and stems, leaving small round pits and holes. Beetles hop quickly off the plant when disturbed. Eggs are laid in soil near the plant. Tiny white larvae feed on root hairs and pupate underground. New adults emerge from mid-July through early August and feed throughout August. Spring crops are damaged by over-wintered adults, while fall crops are damaged by summer adults, but it may be difficult to distinguish the generations when pressure is severe. Feeding generally declines in September, as adults leave fields for overwintering. There may be a small second generation of adults, which emerges in late September. Heavy feeding can kill seedlings, and moderate damage can stunt growth, delay maturity, reduce yield, and make crops unmarketable. Crops with more waxy leaves (Brassica oleracea such as cabbage, broccoli, and kale) are less attractive and feeding is more restricted to leaf margins, especially as crop matures. Crops with glossy leaves (e.g. B. rapa such bok choy, Napa cabbage, or B. juncea such as mustard) are highly attractive; the whole leaf is damaged and the crop is susceptible until harvest.

Escape peak adult activity and avoid the buildup of high populations by rotating spring crops as far as possible from last season's fall brassica crops, and planting late-season crops far from early brassicas. Where feasible, avoiding all early brassicas (until July) can be used to break the reproductive cycle. Incorporate and till crops immediately after harvest to expose and kill larvae and pupae. Provide adequate water and nutrients for crop growth. Avoid soil compaction. Floating row covers provide excellent protection of the crop if well secured with soil or bags around all edges immediately after seeding or transplanting. Remove and replace the same day for cultivation, as needed. Use attractive brassica types (B. rapa or B. juncea) on borders or within the field as a trap crop to draw beetles from less attractive types. Spray the trap crop to suppress beetles in the whole field, and to protect the trap crop for harvest. Scout across the field by counting beetles from above, then under the leaves, and estimating % leaf damage. Because brassica crops differ greatly in susceptibility and attractiveness there is no fixed economic threshold that applies to all crops and crop stages. A working threshold of 1 beetle per plant or >10% average leaf damage on 50% of the plants has proved effective in leafy greens and early stages of heading brassicas. Repeated applications may be needed if pressure is high.

• alpha-cypermethrin (Fastac* EC): 2.2 to 3.8 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.
• azadirachtin (Azatin O^OG): 4 to 16 oz/A foliar or drench, 4 to 16 oz/100 gal in greenhouses; PHI 0d, REI 4h, Bee: L, Group UN. When using lower rates, combine with adjuvant for improved spray coverage and translaminar uptake.
• azadirachtin & pyrethrins (Azera^OG): 16 to 56 oz/A foliar, drench, and greenhouse applications; PHI 0d, REI 12h, Bee: M, Groups UN & 3A.
• beta-cyfluthrin (Baythroid* XL): 2.4 to 3.2 oz/A; PHI 0d, REI 12h, Bee: H, Group 3A. Cabbage flea beetle only.
• bifenthrin (Brigade* 2EC): 2.1 to 6.4 oz/A; PHI 7d, REI 12h, Bee: H, Group 3A.
• carbaryl (Sevin XLR Plus): 0.5 to 1 qt/A; PHI 3d cabbage, cauliflower, broccoli, Brussel sprouts, kohlrabi, 14d kale, collards, Chinese cabbage, mustard, REI 12h, Bee: H, Group 1A.
• cryolite (Prokil Cryolite): 8 to 16 lb/A; PHI 7d, REI 12h, Bee: L, Group UN. Broccoli, Brussels sprouts and cauliflower only. 
• cyantraniliprole (Exirel): 13.5 to 20.5 oz/A; PHI 1d, REI 12h, Bee: H, Group 28.
• cyantraniliprole (Verimark):  6.75 to 13.5 oz/A at planting, 6.75 to 10 oz/A chemigation; PHI 1d chemigation, REI 4h, Bee: H, Group 28. 
• cyclaniliprole (Harvanta): 16.4 fl oz/A; PHI 1d, REI 4 h, Bee: H, Group 28.
• dinotefuran (Venom): 1 to 4 oz/A for foliar application to head and stem brassicas, 2 to 3 oz/A for foliar application to leafy brassicas; PHI 1d, REI 12h, Bee: H, Group 4A.
• esfenvalerate (Asana* XL): 5.8 to 9.6 oz/A; PHI 3d, 7d collards, REI 12h, Bee: H, Group 3A. For broccoli, cabbage, cauliflower, Chinese cabbage, collards only.
• fenpropathrin (Danitol* 2.4EC): 10.66 to 16 oz/A; PHI 7d, REI 24h, Bee: H, Group 3. For head and stem brassicas only. Do not apply during bloom or if bees are actively foraging. May be combined with Belay (see label for rates).
• gamma-cyhalothrin (Declare*): 1.02 to 1.54 oz/A; PHI 1d, REI 24h, Bee: H, Group 3A. Head and stem brassicas only.
• imidacloprid (Admire Pro): 1.3 oz/A; PHI 7d foliar, REI 12h, Bee: H, Group 4A. Foliar applications only.
• kaolin (Surround WP^OG): 25 to 50 lb/A or 0.25 to 0.5 lb/gal; PHI 0d, REI 4h, Bee: L. Suppression and repellence only. May be applied to transplants prior to setting in field. Use on seedlings and young plants. White residue is difficult to wash off leaves and heads; use only on very young leaves or leaves that will not be harvested.
• lambda-cyhalothrin (Warrior* II): 1.28 to 1.92 oz/A; PHI 1d, REI 24h, Bee: H, Group 3A. For head and stem brassicas.
• permethrin (Pounce* 25WP): 6.4 to 12.8 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A. Cabbage and Chinese cabbage only.
• petroleum oil (Suffoil X^OG): 1 to 2 gal/100 gal water; PHI 0d, REI 4h, Bee: L. Apply as needed. For beetle larvae only. 
• pyrethrin (PyGanic EC5.0^OG): 4.5 to 17 oz/A; 0.25 to 0.50 oz/gal, 3 gal/1000 sq ft in greenhouse for backpack sprayers; PHI 0d, REI 12h, Bee: M, Group 3A.
• spinosad (Entrust SC^OG): 4 to 8 oz/A; PHI 1d, REI 4h, Bee: M, Group 5. Suppression only.
• thiamethoxam (Actara): 1.5 to 3 oz/A; PHI 7d leafy brassica greens, 0d head and stem brassicas, REI 12h, Bee: H, Group 4A.
• thiamethoxam (Platinum): 5 to 11 oz/A; PHI 30d, REI 12h, Bee: H, Group 4A. Systemic insecticide used as an in-furrow, banded, drench, or drip irrigation application to the seed/seedling root zone during or after planting/transplanting operations or shanked into root zone after transplanting or establishment.
• tolfenpyrad (Torac): 17 to 21 fl oz/A; PHI 1d, REI 12h, Bee: H, Group 21A.
• zeta-cypermethrin (Mustang*): 2.24 to 4 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.

Onion Thrips (Thrips tabaci)

Onion thrips can be a significant problem on cabbage, where thrips feed on inner leaves of the head which are difficult to target by spraying. Damage may also occur on leafy brassicas such as broccoli, kale and collard, especially fall crops that are planted near a maturing onion crop.  Thrips cause rough, golden or brown scars to form on the underside of open leaves, or produce scars and discolored layers within cabbage heads. Inspection with a 10X lens shows wounds to the epidermis from the rasping mouthparts, and scars from wounds that healed over.  Thrips damage can be confused with oedema, a physiological disorder. See onion thrips in the Onion section for more information on identification, life cycle and management.  Damage is most severe in hot, dry weather.

Tolerant varieties are the most cost-effective means of controlling thrips in cabbage. Varietal resistance is generally not available in other brassicas. Consult your seed suppliers and search recent research trials regarding thrips tolerance on new varieties.

Avoid thrips by not planting cabbage or fall brassica crops near alliums (onion family), or field crops such as alfalfa, clover, wheat, or oat that can harbor large populations of thrips, which may migrate to brassicas when these crops are cut or harvested. Scout young plants for presence and feeding injury. Begin applications when damage is first noticed; in cabbage, apply foliar treatments before heads form. In fall brassicas, the need for thrips controls may coincide with sprays for flea beetle or caterpillars and some insecticides control both.  Repeat applications at 7- to 10-day intervals based on scouting. Use a shorter interval in hot, dry weather. Use spreader-sticker for better coverage. Apply in early evening, using high pressure and 100 gal water/A for best results. Systemic insecticides applied as a side dress up to 4-6 weeks after transplanting may provide adequate control in long-season cabbage. Rotate between insecticide groups to help prevent or delay resistance.

• acetamiprid (Assail 30SG): 4 oz/A; PHI 7d, REI 12h, Bee: H, Group 4A.  Applications during the "cupping" stage of cabbage may be especially helpful in preventing injury.
• alpha-cypermethrin (Fastac* EC): 3.2 to 3.8 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.
• azadirachtin (Azatin O^OG): 4 to 16 oz/A foliar or drench, 4 to 16 oz/100 gal in greenhouses; PHI 0d, REI 4h, Bee: L, Group UN. When using lower rates, combine with adjuvant for improved spray coverage and translaminar uptake.
• Beauveria bassiana (Mycotrol ESO): 8 to 32 oz/A; PHI 0d, REI 4h, Bee: L, Group UN. Thoroughly cover foliage. Takes 7 to 10 days after application to see control.
• beta-cyfluthrin (Baythroid* XL): 0.8 to 1.6 oz/A; PHI 0d, REI 12h, Bee: H, Group 3A.
• bifenthrin (Brigade* 2EC): 2.1 to 6.4 oz/A; PHI 7d, REI 12h, Bee: H, Group 3A.
• Chromobacterium subtsugae strain PRAA4-1 (Grandevo^OG): 2 to 3 lb/A; PHI 0d, REI 4h, Bee: M, Group UN.
• cyantraniliprole (Exirel): 13.5 to 20.5 oz/A; PHI 1d, REI 12h, Bee: H, Group 28. Suppression only.
• cyantraniliprole (Verimark):  10 to 13.5 oz/A at planting, 10 oz/A chemigation; PHI 1d chemigation, REI 4h, Bee: H, Group 28. Suppression only.
• dinotefuran (Safari 20SG): 0.16 to 0.32 dry oz/1,000 sq ft or 7 to 14 oz/A; REI 12h, Bee: H, Group 4A. Broccoli, Brussels sprouts, cabbage, cauliflower and kohlrabi transplants only while in greenhouse. Not for field use. Suppression only.
• gamma-cyhalothrin (Declare*): 1.02 to 1.54 oz/A; PHI 1d, REI 24h, Bee: H, Group 3A. Suppression only. Head and stem Brassicas only.
• imidacloprid (Admire Pro): 4.4 to 10.5 oz/A; PHI 21d soil, REI 12h, Bee: H, Group 4A. Soil applications only.
• insecticidal soap (M-Pede^OG): 1.25 to 2.5 oz/gal water; PHI 0d, REI 12h, Bee: L. Spray to wet all infested plant surfaces. May need to make repeated applications. For enhanced and residual control, apply with companion labeled inseccticide.
• lambda-cyhalothrin (Warrior* II): 1.28 to 1.92 oz/A; PHI 1d, REI 24h, Bee: H, Group 3A. For head and stem brassicas. Suppression only.
• novaluron (Rimon 0.83EC): 12 oz/A; PHI 7d, REI 12h, Bee: L, Group 16B. Most effective on immature stages. Not labeled for collards and kale. 
• permethrin (Pounce* 25WP): 3.2 to 6.4 oz/A for Brussels sprouts, cauliflower; 3.2 to 12.8 oz/A for broccoli, Chinese broccoli; PHI 1d, REI 12h, Bee: H, Group 3A. Not for other brassicas.
• petroleum oil (Suffoil X^OG): 1 to 2 gal/100 gal water; PHI 0d, REI 4h, Bee: L. Apply as needed.
• pyrethrin (PyGanic EC5.0^OG): 4.5 to 17 oz/A; 0.25 to 0.50 oz/gal, 3 gal/1000 sq ft in greenhouse for backpack sprayers; PHI 0d, REI 12h, Bee: M, Group 3A.
• spinetoram (Radiant SC): 6 to 10 oz/A; PHI 1d, REI 4h, Bee: M, Group 5. Efficacy improves with the addition of an adjuvant.
• spinosad (Entrust SC^OG): 4 to 10 oz/A; PHI 1d, REI 4h, Bee: M, Group 5. Efficacy improves with the addition of an adjuvant.
• sulfoxaflor (Closer SC): 5.75 oz/A; PHI 3d, REI 12h, Bee: H, Group 4C. Suppression only.
• thiamethoxam (Actara): 3 to 5.5 oz/A; PHI 7d leafy brassica greens, 0d head and stem brassicas, REI 12h, Bee: H, Group 4A.
• thiamethoxam (Platinum): 5 to 11 oz/A; PHI 30d, REI 12h, Bee: H, Group 4A. Systemic insecticide used as an in-furrow, banded, drench, or drip irrigation application to the seed/seedling root zone during or after planting/transplanting operations or shanked into root zone after transplanting or establishment.
• zeta-cypermethrin (Mustang*): 3.2 to 4 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.

Slugs

There are several species of slugs that damage vegetable crops in New England, including grey garden, banded, marsh and spotted garden slugs.  They may be dark gray, black, yellow or brown, covered with spots, and range from ¾ to nearly 4" long. Eggs may be laid several times per year, and slugs reach maturity in 3-6 months. They can become abundant in low- and no-till situations, in land that was recently fallow, along hedgerows, or wherever plant debris, mulches, stones or boards provide cover and daytime hiding places. Slugs usually feed at night but may also feed during the day during prolonged periods of cloudy wet weather. They are attracted to succulent leaves in moist environments, such as cabbage, pak choi, and Chinese cabbage. They will also feed on fruiting crops such as tomato, pepper and eggplant. Damage appears as shredded foliage or shallow fruit holes. They have a rasp-like tongue that wears a hole through the leaf instead of making a clean cut like a caterpillar or beetle. On some thick-leaved brassicas such as cabbage, the hole will appear larger on one leaf surface and taper to a smaller hole in the opposite surface.  Scout by looking for silvery slime trails on leaves or turn over soil clods or debris to find slugs during daylight hours, or scout plants after dusk. Slug populations can also be monitored with unbaited traps consisting of 6 in. deep holes covered with foil-covered shingles, which provide a cool hiding place during the day. To control slugs use habitat and cultural management supplemented by handpicking or trapping (on a small scale), repellents and toxic baits.  Grow plants away from moist, shaded habitats, use clean cultivation, control weeds, and eliminate hiding places.  Use trickle irrigation instead of overhead to reduce humidity and moist surfaces. On a small scale, handpick slugs after dusk using gloves and drop slugs in soapy water; repeat for several days. Baits should be applied to the ground near infested plants. It may be necessary to reapply after a rain, or make multiple applications when populations are high.

• iron phosphate (Sluggo: Snail and Slug Bait^OG): 20 to 44 lb/A; PHI 0d, REI 0h, Bee: L, Group 9B. Apply around perimeter, scatter around base of plants, or band down rows. Apply to moist soil in the evening.
• metaldehyde (Deadline Bullets): 20 to 40 lb/A; REI 12h, Bee: L. Soil surface treatment broadcast pre-planting, or band treatment between rows after formation of edible parts. Apply to moist soil in the evening. Do not apply directly to or contaminate edible portions of plants.

Swede Midge (Contarinia nasturtii)

A serious pest of crucifers in Europe. Recently introduced into North America, currently established in northwestern Vermont, with range expanding southward and eastward. Adults are tiny (1/16 in.), weak-flying, brown flies, while larvae are translucent maggots when small and turn yellow as they grow to 1/8 inch. They spend the winter as pupae in the top 2 in. of soil. Maggots infest the tissue near the growing tip and produce malformed plants with brown corky tissue, galls, no-heads, multi-heads, and twisted leaf petioles. Damage is most severe on broccoli, Chinese broccoli, Brussels sprouts, cauliflower and brassica greens. There may be 3-4 generations each year. Scout young plants near field borders and tree lines prior to heading or at the pre-cupping stage. Avoid importing infested plants by using New England-grown transplants. Use a 3-year crop rotation. Plant spring brassicas at least 1/2 mile from fall brassica fields. Deep plowing destroys pupae. Spring plantings may avoid peak populations later in the season. If possible, plant away from tree lines that shelter weak-flying adults. Report and confirm infestations to a state IPM specialist or to the diagnostic lab.

• acetamiprid (Assail 30SG): 4 oz/A; PHI 7d, REI 12h, Bee: H, Group 4.
• azadirachtin & pyrethrins (Azera^OG): 16 to 56 oz/A foliar, drench, and greenhouse applications; PHI 0d, REI 12h, Bee: M, Groups UN & 3A.
• Burkholderia spp. strain A396 (Venerate XC^OG): 2 to 4 qt/A; PHI 0d, REI 4h, Bee: M, Group UN. Suppression only.
• spirotetramat (Movento): 4 to 5 oz/A; PHI 1d, REI 24h, Bee: M, Group 23. Must be tank-mixed with a spray adjuvant with spreading and penetrating properties to maximize leaf uptake and sytemicity; don't use sticker adjuvants. Controls immature stages; may also reduce adult fertility.

Weed Control

NOTE:  For the herbicides listed below, one product trade name and formulation is provided for each active ingredient along with preharvest interval (PHI), restricted entry interval (REI), resistance management group number, and example of rates and special instructions. In many cases, there are other products available with the same active ingredient. However, not all products with the same active ingredient are registered for use in a crop. Always check the product label to be sure that the crop is listed before using. 

Stale Seedbed

See Stale Seedbed Technique for information on the use of these herbicides.

• glyphosate (Roundup Power Max): REI 12h, Group 9. Rate based on target weed species. See label for info.
• paraquat (Gramoxone SL 2.0*): restricted use. REI 12h, Group 22. Snap and lima only. Use 2–4 pts/A. May be fatal if swallowed or inhaled. Applicators must complete an EPA-approved paraquat training listed on the following website https://www.epa.gov/pesticide-worker-safety/paraquat-dichloride-training-certified-applicators. The training must be completed a minimum of every three years.
• pelargonic acid (Scythe): PHI 1d, REI 12h, Group 17. Use a 3 -10% solution (3 to 10 gallons per 100 gallons).

Herbicides Used Preemergence, before weeds germinate

• bensulide (Prefar 4E): REI 12h, Group 0.  Apply 5 to 6 qt/A.  Can be preplant incorporated by shallow cultivation (1-2”) or applied preemergence and incorporated by irrigation within 36 hours of application. Grass control only; should be supplemented with cultivation or another registered herbicide for broadleaf control. See label for rotation restrictions.
• DCPA (Dacthal W-75): REI 12h, Group 3.  Apply 6 to 14 lb/A at seeding or transplanting. Can be sprayed over transplants without injury. For collards, kale, broccoli raab and other leafy crops apply at seeding.  Will not control ragweed, galinsoga or smartweed. Use lower rates on sandy soils.
• napropamide (Devrinol 2-XT): REI 12h, Group 0. Apply up to 2 qt/A to a weed-free surface. A higher rate is permitted for use on broccoli in Maine only.  See label for details.  May be applied to direct seeded and transplanted crop as preplant incorporated or as a surface spray after planting. Must be shallow incorporate or incorporated thoroughly with irrigation if adequate rainfall does not occur within 24 hours of application (sufficient water to wet soil to a depth of 2" to 4").
• oxyfluorfen (Goal): REI 24h, Group 14.  Pre-transplant application only to broccoli, cabbage, and cauliflower.  Apply 1 to 2 pt/A after completion of soil preparation but prior to transplanting. Do not incorporate. May cause temporary crop injury, and can cause severe crop injury if not applied properly. Read product label carefully before applying. 
• pendimethalin (Prowl H2O): PHI 60d for broccoli, PHI 70d for all others, REI 24h, Group 3.  Use as a postemergence-directed spray on the soil beneath plants and between vegetative rows of brassica head and stem vegetables. Apply a single application of up to 2.1 pt/A.  For transplants, apply when crop is at the 2 to 4-leaf stage 1 to 3 days after transplanting.  For direct-seeded crops, apply when crop is at the 2 to 4-leaf stage.  Apply DO NOT spray foliage or stems because crop injury will occur. If rainfall or irrigation does not occur, mechanically incorporate to activate the herbicide. Apply before weed germination. Emerged weeds will not be controlled.
• s-metolachlor (Dual Magnum): REI 12h, Group 15.  MASSACHUSETTS AND NEW HAMPSHIRE: Broccoli, cabbage, and leafy brassica greens only.  MAINE: cabbage only. Make sure the label for your state is available for download before using this product. This is a restricted label available only to growers who apply through the website www.syngenta-us.com/labels/indemnified-label-login and agree to a waiver of liability. Main target weeds for this registration are galinsoga and yellow nutsedge.
• trifluralin (Treflan HFP): REI 12h, Group 3. Incorporate 1 to 1.5 pt/A before seeding crops, or 1 to 2 pt/A before transplanting (broccoli, brussels sprouts, cabbage, and cauliflower). For greens (collard, kale, mustard and turnip), can be used before seeding only. Select rate based on soil texture, see label for details.  Must be incorporated into the top 2 to 3 inches of the final seedbed within 24 hours of application.  Disc twice after spraying for satisfactory incorporation. See label for info on incorporation recommendations based on different equipment and single pass incorporation.Little or no control of ragweed, galinsoga, mustard or nutsedge.

Herbicides Used Postemergence, after weeds germinate

• carfentrazone (Aim EC): REI 12h, Group 14.  Aim is a burndown herbicide and will injure any foliage it comes into contact with. Apply Aim to row middles of emerged crops with hooded sprayers to control emerged weeds, including crops grown on mulch or plastic.  Prevent any spray from contacting the crop, or injury will occur.  For best results, make application to actively growing weeds up to 4 inches tall and rosettes less than 3 inches across. Good coverage is essential for good control.  Apply up to 2 oz/A per application, and do not exceed a total of 6.1 oz/ per season. 
• clethodim (Select Max): PHI 30d, PHI 14d for leafy brassica greens, REI 24h, Group 1.  Will control grass weeds only. Apply to actively growing grasses.  See label for rate selection.  Multiple applications permitted of 9 to 16 oz/A per application, minimum 14-days between applications, not to exceed 64 oz/A per year.  Add 0.25% v:v nonionic surfactant (1 qt per 100 gal of spray).  Can also be used as a spot-spray by mixing 1/3-2/3% (0.44 to 0.85 oz per gallon) Select Max and 0.25% v:v nonionic surfactant (0.33 oz per gallon).  Spray to wet, but do not allow runoff of spray solution.
• clopyralid (Stinger): PHI 30d, REI 12h, Group 4. Apply 1/4 to ½ pt/A for postemergence control of common ragweed, galinsoga, prickly lettuce, sweet clover, and wild buckwheat and suppression of sowthistle. Stinger is very effective on small seedling annual and emerging perennial weeds less than 2" to 4" tall, but is less effective and takes longer to work when weeds are larger. Spray additives are not needed or required by the label and are not recommended. Stinger is a postemergence herbicide with some soil residual activity. See label for crop rotation restrictions, or injury may occur from herbicide carryover. Make 1 to 2 applications a year, but do not exceed 1/2 pt/A per year.
• pelargonic acid (Scythe):  PHI 1d, REI 12h, Group 17. Use a 3 -10% solution (3 to 10 gallons per 100 gallons). Use a 3 to 5% solution for annual weeds, a 5 to 7% solution for biennial and perennial weeds, and 7 to 10% solution for maximum burndown. Delivery rate for boom applications should be 75 to 200 gals of spray solution per acre; complete coverage of weed foliage is essential. Use a DIRECTED/ SHIELDED SPRAY; contact with crop will cause injury. For hand-held equipment, spray to completely wet all weed foliage but not to the point of runoff. Repeat applications as necessary. Tank mixes are allowed with this product. See label for complete details.
• sethoxydim (Poast): PHI 30d, PHI 14d for leafy brassica greens, REI 12h, Group 1.  Controls grass weeds only.  Apply to actively growing grasses (see product label for susceptible stage).  Maximum 1.5 pt/A per application, minimum 14-days between applications.  Do not exceed 3 pt/A per year. Use with crop oil concentrate (2.0 pt/A) or methylated seed oil (1.5 pt/A).  Note that crop oil can cause injury under hot and humid conditions.  Can also be used as a spot-spray by mixing 1-1.5% (1.3 to 1.9 oz per gallon) Poast and 1% v:v crop oil concentrate (1.3 oz per gallon).  Spray to wet, but do not allow runoff of spray solution.

Note About Other Labeled Herbicides: Other products are labeled for use in brassicas but limited local data are available for these and/or they are not recommended in our region due to potential crop injury concerns. These include clomazone (Command 3ME) and sulfentrazone (Zeus and others).

Physiological Disorders

Buttoning and Lack of Heads (Broccoli and Cauliflower)

Buttoning refers to premature formation of broccoli or cauliflower heads. It occurs when transplants do not have enough leaves to support a head of a marketable size. Buttoning is most common when young plants are transplanted prior to hardening off or into suboptimal field conditions. Early varieties and older transplants are most susceptible. Other stress factors such as low fertility, low moisture micronutrient deficiencies, or disease and insects can also be causes. Strong healthy plants lacking heads can occur due to periods of extremely warm weather (days over 86ºF and nights over 77ºF).

Bracts (Leaves) in Cauliflower or Broccoli Heads

High temperatures and/or low soil moisture can result in the formation of bracts, small leaves, between segments in the heads of cauliflower and broccoli. Choose heat-tolerant varieties to avoid bract formation in heads. Maintain uniform soil moisture.

Brown Bead (Broccoli)

The disease is caused by a combination of environmental and genetic factors. Reduced calcium uptake due to low transpiration rates under extended wet conditions followed by warm temperatures and rapid growth can result in this condition. Brown bead occurs when individual flower buds abort under warm, dry conditions. It is recomended to grow less susceptible varieties. It is best to grow a mix of varieties with different maturation rates to reduce the risk of losing the entire crop due to adverse weather conditions.

Oedema of Cabbage

Oedema (edema) is a physiological response of the plant to excessive soil moisture during periods of cool nights and warm, humid days. Many small scabby lesions form on the underside of the cabbage leaves. Avoid irrigation during times when day-night temperature variations are great. Oedema may be confused with thrips damage.

Ricing or Fuzziness of Heads (Cauliflower)

The development of cauliflower curds that appear fuzzy is called ricing. Ricing can be caused by exposure of the developing curds to high temperatures or direct exposure to sun, rapid growth after head formation, high humidity, and high nitrogen fertility.

Tipburn

Tipburn is a result of localized calcium deficiency in leaf tips, which can occur due to irregular soil moisture content or low plant transpiration rates even when soil calcium levels are high. Providing consistent irrigation and taking measures to prevent root-compromising disease can help reduce incidence of tipburn.

Yellow Beads in Broccoli

Yellowing of florets may be due to an over-mature head, high storage temperatures after harvest, or exposure to ethylene. 

Hollow Stem (Broccoli and Cauliflower)

This disease is typically associated with boron deficiency, but may also occur when excessive nitrogen encourages rapid growth. Tissue or soil testing can detect boron deficiency. Brown discoloration of heads may accompany this condition.