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 27 and Insecticides Alphabetical Listing by Trade Name for more information on these insecticides.

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 Regulations 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.

Note: For best results with aerosols, apply when air temperature in the greenhouse is 70°F to 80°F. Keep vents closed and fans off during treatment. Ventilate greenhouse before entering DO NOT perform this operation alone.

PESTICIDE USE IN GREENHOUSES AND HIGH TUNNELS:

Pesticides can be used on high tunnel and greenhouse crops if: 1) the crop and pest/disease is on the label, AND the products specifically says it can be used in the greenhouse; OR 2) the crop and pest/disease is on the label, AND the product is ‘silent’ about use in the greenhouse in the greenhouse. Products that specifically prohibit greenhouse use cannot be used in greenhouses or high tunnels regardless of the crops or pests/diseases listed on the label.

Aphids, Two-spotted Spider Mite, Thrips, Fungus Gnats

Scouting and preventative, timely releases of biological controls can be effective in managing aphids, thrips, spider mites and fungus gnats in greenhouse tomato. See potato aphid in the Potato insect control, green peach aphid in the Pepper insect control, spider mites in Tomato, Outdoor. Refer also to the Transplant Insect and Mite Management section for more information about greenhouse pests, including Table 19 for biological control guidelines and Table 21 about insecticides labeled for vegetable transplants in the greenhouse. Note that some of the products listed in these tables are only labeled for transplants, not crops to be sold such as greenhouse tomatoes.

Please refer to the following guides for more information on the biology and monitoring of these pests in greenhouse crops and how to integrate cultural practices, biological control and pesticides:  The New England Greenhouse Floriculture Guide and the Penn State manual Greenhouse IPM with an Emphasis on Biocontrols. 

• abamectin (Agri-Mek SC): 1.75 to 3.5 oz/A; PHI 7d, REI 12h, Bee: H, Group 6. For two-spotted spider mite and thrips only. Must be mixed with a non-ionic activator type wetting, spreading, and/or penetrating spray adjuvant. Do not use binder or sticker type adjuvant.
• acequinocyl (Kanemite 15SC): 31 oz/A; PHI 1d, REI 12h, Bee: L, Group 20B. For two-spotted spider mite only. Do not use less than 100 gal water/A. Use of an adjuvant or surfactant is prohibited.
• 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.
• Bacillus thuringiensis subsp. israelensis (Gnatrol WDG^OG): 3.2 to 6.4 oz/100 gal for light infestations, 13 to 26 oz/100 gal for heavy infestations; REI 4h, Bee: L, Group 11. Use higher rate for heavy infestation. Apply as soil drench to flats to control larvae. Fungus gnat larvae only.
• Beauveria bassiana (Mycotrol ESO^OG): 0.5 to 1 lb/100 gal for aphids, 1 to 2 lb/100 gal for thrips; PHI 0d, REI 4h, Bee: L, Group UN. For aphids and thrips. 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.
• bifenazate (Floramite SC): 4 to 8 oz/100 gal water (apply 1 to 4 qt mix/100 sq ft or 100 to 400 gal/A); PHI 3d, REI 12h, Bee: L, Group 20D. Mites on greenhouse tomatoes only. Apply when mites first appear.
• Burkholderia spp. strain A396 (Venerate XC^OG): 2 to 4 qt/A for aphids and mites, 1 to 4 qt/A for thrips; PHI 0d, REI 4h, Bee: M. Group UN. Suppression only. Not for fungus gnats. 
• chlorfenaspyr (Pylon Miticide-Insecticide): 6.5 to 13 oz/A for mites, 9.8 to 13 oz/A for thrips; PHI 0d, REI 12h, Bee: M, Group 13. Mites and thrips only.
• Chromobacterium subtsugae strain PRAA4-1 (Grandevo^OG): 2 to 3 lb/A; PHI 0d, REI 4h, Bee: M. Group UN. Not for fungus gnats. 
• cyantraniliprole (Exirel): 13.5 to 20.5 oz/A; PHI 1d, REI 12h, Bee: H, Group 28. Suppression of thrips only.
• dinotefuran (Venom): 1 to 4 oz/A foliar or 5 to 7.5 oz/A soil; 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. Do not apply to varieties with fruit that is less than 2" such as cherry or grape tomatoes. Do not apply to vegetables grown for seed.
• imidacloprid (Admire Pro): 0.6 oz/1,000 plants; PHI 0d, REI 12h, Bee: H, Group 4. Aphids only. Use on mature plants only. Apply in a minimum of 16 gal water. Do not apply to plants grown in non-soil media.
• 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. Not for fungus gnats. Repeat application every 2 to 3 days until pest is under control. For enhanced and residual control, apply with companion labeled aphicide.
• Metarhizium anisopliae Strain F52 (Met 52 EC): 40 to 80 oz/100 gal (drench), 8 to 64 oz/A (foliar); PHI 0d, REI 4h, Bee: L, Group UN. Thrips and mites only.
• petroleum oil (Suffoil X^OG): 1 to 2 gal/100 gal water; PHI 0d, REI 4h, Bee: L. Apply as needed. Not for fungus gnats.
• 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 (Distance IGR): 2 oz/100 gal as a surface drench to top 1" of soil media, 3 to 6 oz/100 gal as a heavy coarse spray to soil surface for fungus gnats and shore flies; 6 oz/100 gal for suppression of aphids and western flower thrips; PHI 1d, REI 12h, Bee: L, Group 7D. Do not apply to tomato varieties less than 1" in diameter, such as cherry or grape tomatoes.
• sulfoxaflor (Closer SC): 1.5 to 2 oz/A; PHI 1d, REI 12h, Bee: H, Group 4C. Aphids only. Do not apply between 3 days prior to bloom and until after petal fall. Do not treat seedling plants grown for transplant.

Hornworms, Fruitworms, Loopers, Armyworm

Hornworms are large green caterpillars with white stripes along the sides that may grow up to 4" long. Look for the large pellet-like fecal droppings on the plastic under the plants, defoliation of leaves with only bare stems remaining, or surface feeding scars on green fruit. Caterpillar infestations usually begin in July and may extend through September. Spot–treat areas of the greenhouse. Use selective insecticides to preserve natural enemies and avoid secondary pest outbreaks (i.e. aphids). See cabbage looper in the Cabbage insect control, and tomato fruitworm and tomato hornworm in Tomato (Outdoor) insect control for more information on these pests. Several species of armyworm feed on tomato fruits. See pepper section for more on armyworm.

• 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. For young larvae.
• Bacillus thuringiensis subsp. 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 subsp. 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).
• Burkholderia spp. strain A396 (Venerate XC^OG): 1 to 4 qt/A; PHI 0d, REI 4h, Bee: M. Group UN.
• chlorfenaspyr (Pylon Miticide-Insecticide): 6.5 to 13 oz/A; PHI 0d, REI 12h, Bee: M, Group 13.
• Chromobacterium subtsugae strain PRAA4-1 (Grandevo^OG): 1 to 3 lb/A; PHI 0d, REI 4h, Bee: M. Group UN.
• novaluron (Rimon 0.83EC): 9 to 12 oz/A; PHI 1d, REI 12h, Bee: L, Group 16B. Most effective on 1st and 2nd instars.
• 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.

Slugs

• iron phosphate (Sluggo: Snail and Slug Bait^OG): 20 to 44 lb/A, 0.5 to 1 lb/1,000 sq ft.,  or 0.5 tsp/9" pot; PHI 0d, REI 0h, Bee: L, Group 9B. Apply to moist soil in evening. Scatter on soil around plants, or in and around pots.
• metaldehyde (Deadline Bullets): 25 lbs/A; PHI 0d, 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.

Spotted Wing Drosophila (Drosophila suzukii)

Spotted Wing Drosophila (SWD) is an invasive pest that first arrived and spread throughout New England in 2011.  It is primarily a pest of fruit crops, where the ability to oviposit in sound fruit (especially blueberry, raspberry, cherry, and peach) makes it a more serious pest than native fruit flies.  SWD is deterred from laying eggs in sound tomato fruit by the strength of the tomato skin. However, where there are cracks and other openings, eggs are laid and larvae build up in fruit, liquefying the fruit contents and leaving nothing but an empty skin. Thus the management of cracked fruit is key to preventing buildup of SWD populations in tomato and possible contamination of cracked tomato fruit and containers post-harvest. Infestation can occur in the field or in high tunnels and greenhouse tomatoes. Buildup in tomato can increase the risk to more susceptible crops on the farm.

Cultural practices are likely to be more effective than insecticides in reducing these risks. Avoid planting varieties that are prone to cracking. When possible, maintain steady soil moisture to avoid a surge in uptake of water by tomato plants, which increases cracking.  Remove culls from the greenhouse. Minimize cracked fruit by harvesting before fruit is completely ripe--especially with cherry tomatoes which are prone to cracking. The same postharvest practices that you already use to minimize native fruit flies will also help with SWD. Keep packing areas clean and remove culls daily.  Keep cherry tomatoes in shallow containers for easier sorting. Compost and cover culled, injured or cracked fruit. Store fruit at the coolest temperatures suitable for tomato to delay egg hatch, if eggs are present.

Follow Extension monitoring alerts to know when SWD is starting to build up in your area.  Currently, there are no thresholds for use of insecticides to control SWD in tomato.  Few insecticides are registered specifically for control of SWD on tomato. Consult Extension SWD materials for updates on efficacy of products labeled for tomato.

• malathion (Malathion 57 EC): 2.5 pt/A; PHI 1d, REI 12h, Bee: H, Group1B.

Variegated Cutworm (Peridroma saucia)

Variegated cutworms will feed on leaves, but will also chew shallow or deep holes in the fruit during mid- to late summer. Caterpillars are brownish-grey, with diamond-shaped marks along the back and light lines along the sides. They are up to 2" long. Scout fruit for damage during harvest. Spray tomatoes if 1% of the plants are infested with variegated cutworms. For best results, make application after dark. Thorough coverage of the foliage is needed for good control. Neem (azadirachtin) interrupts larval development and acts as a feeding deterrent. See Tomato (Outdoor) section for more information on variegated cutworm.

• 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. For larvae only.
• Burkholderia spp. strain A396 (Venerate XC^OG): 1 to 4 qt/A; PHI 0d, REI 4h, Bee: M. Group UN.
• Chromobacterium subtsugae strain PRAA4-1 (Grandevo^OG): 1 to 3 lb/A; PHI 0d, REI 4h, Bee: M. Group UN.
• 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.

Whiteflies, Greenhouse (Trialeurodes vaporariorum) and Sweet Potato (Bemisia tabaci)

The primary whitefly species in greenhouses are the greenhouse whitefly (Trialeurodes vaporariorum) and sweet potato whitefly B-biotype (Bemisia tabaci), which is also known as the silverleaf whitefly (Bemisia argentifolii). Greenhouse whitefly is more common on greenhouse tomatoes, but both species occur in greenhouses, and correct identification of which species is present is important in order to select effective biological controls. The host range of greenhouse whitefly includes many ornamentals and vegetables; among greenhouse-grown vegetables the most common hosts are tomato, eggplant and cucumber. In the field, bean, cucumber, cantaloupe, lettuce, squash, tomato and eggplant are good hosts, with cabbage, sweet potato, pepper and potato less suitable. Sweet potato whitefly also has a wide host range, with cucurbit and sweet potato crops favored as well as fruiting crops.

Greenhouse whitefly adults are more active at temperatures around 75ºF (24ºC). Adults are winged, white, and 1/16" (2.0 mm) long. Greenhouse whitefly adults hold their wings flat, parallel to the top of the body. Females lay more than 20 eggs in a small circle. Newly laid eggs are white and eventually turn gray. Young nymphs (crawlers) are white, have legs and antennae, and move short distances before locating suitable places to initiate feeding. More mature nymphs (third and fourth instars) are typically found on the lower leaves. Pupae do not feed, and have distinct visible red eyes. Greenhouse whitefly pupae may possess long waxy filaments encircling the outer edge, and are elevated in profile with vertical sides, resembling “cakes” on leaf surfaces.

Sweet potato whitefly B-biotype adults prefer temperatures >80ºF (26ºC).The adults are yellow and smaller than greenhouse whitefly. Their wings are tilted, and held roof-like over their bodies. Adult females live up to 6 weeks, and produce up to 200 eggs, which are randomly laid in small clusters on new plant growth. Newly laid eggs are white and then turn amber-brown. Young nymphs (crawlers) have legs and antennae and move short distances before locating suitable places to initiate feeding. More mature nymphs (third and fourth instars) are typically found on the lower leaves. Sweet potato whitefly B-biotype nymphs are yellow, oval and dome-shaped, and do not possess long waxy filaments.

Large populations of whiteflies cause leaves to turn yellow, appear dry, or fall off plants.  Honeydew excreted by whiteflies encourages growth of black sooty mold, and also attracts ants that interfere with natural enemies of other pests.

Avoid overfertilizing crops as this increases their attractiveness to adult whiteflies. Whiteflies may be introduced into greenhouses on infested cuttings or plants arriving from outside sources.  Carryover or stock plants may also be a source of whiteflies. Using appropriate sanitation practices like weed removal helps alleviate whitefly problems in subsequent cropping cycles. Manage whiteflies during transplant production to avoid introducing whiteflies to production greenhouses or to the field; for more information on controls on transplants see whiteflies in the Insect and Mite Management section of Vegetable Transplants.

Scout weekly by checking the undersides of 1 to 2 leaves on 10 to 20 plants throughout the greenhouse.  Use yellow sticky cards to capture whitefly adults. Hang traps near the tops of the plants, 1 to 4 cards every 1,000 sq ft of greenhouse. Check and replace weekly, recording the number of adults per card. Use this information to decide if natural enemy releases or insecticides are needed.

As with all biological controls, it is important to begin releases early, before the pest builds up, and continue releases as the crop grows. The parasite Encarsia formosa has been successfully used to control greenhouse whiteflies on greenhouse tomato and other crops.  The parasite Eretmocerus eremicus is used for control of sweet potato whitefly.  Please consult the following guides for more information on the biology and monitoring of whiteflies in greenhouse crops and how to integrate cultural practices, biological control and pesticides:  The New England Floriculture Guide and the Penn State manual Greenhouse IPM with and Emphasis on Biocontrols. 

• buprofezin (Talus 70DF): 6 to 9 oz/100 gal; PHI 1d, REI 12h, Bee: L, Group 16. Apply when population level reaches economic threshold. Good coverage is essential. Applications must be made with high volume, low volume, or ultra-low volume ground equipment only.
• Burkholderia spp. strain A396 (Venerate XC^OG): 2 to 4 qt/A; PHI 0d, REI 4h, Bee: M. Group UN.
• 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. For best performance, use an effective adjuvant. 
• dinotefuran (Venom): 1 to 4 oz/A foliar or 5 to 7.5 oz/A soil; PHI 1d foliar, 21d soil, REI 12h, Bee: H, Group 4A. Do not apply to varieties with fruit that is less than 2", such as cherry or grape tomatoes. Do not apply to vegetables grown for seed. 
• imidacloprid (Admire Pro): 0.6 oz/1,000 plants; PHI 0d, REI 12h, Bee: H, Group 4. Use on mature plants only. Apply in a minimum of 16 gal water. Do not apply to plants grown in non-soil media.
• 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. Repeat application every 2 to 3 days until pest is under control.
• Metarhizium anisopliae Strain F52 (Met 52 EC): 40 to 80 oz/100 gal (drench), 8 to 64 oz/A (foliar); PHI 0d, REI 4h, Bee: L, Group UN.
• 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.
• pyriproxyfen (Distance IGR): 6 oz/100 gal; PHI 1d, REI 12h, Bee: L, Group 7D. Apply as a foliar spray. Do not apply to tomato varieties less than 1" in diameter, such as cherry or grape tomatoes.