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.

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.

Allium Leafminer (Phytomyza gymnostoma)

For more information on this pest and for cultural and chemical controls, see Allium Leafminer in the leek section.

abamectin (Agri-Mek* SC): 1.75 to 3.5 fl oz/A; PHI 30d, REI 12h, Bee: H, Group 6. Make 2 consecutive applications then rotate to a different mode of action. Make at least 2 consecutive applications of another mode of action before making additional Agri-Mek SC applications. Insect control can be reduced if used with a sticker or binder type product.

azadirachtin (Azatin OOG): 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.

cyantraniliprole (Exirel): 13.5 to 20.5 fl oz/A; PHI 1d, REI 12h, Bee:H, Group 28. Use with an adjuvant to maximize efficacy. Spreading and penetrating adjuvants can cause negative crop response.

cyromazine (Trigard): 2.66 oz/A; PHI 7d, REI 12h, Bee: H, Group 17. Apply when leafminers first appear. Do not apply more than 6 times or 1 lb/A per calendar year.

dinotefuran (Scorpion 35SL): 5.25 to 7 fl oz/A foliar, 8.75 to 10.5 fl oz/A soil; PHI 1d, REI 12h, Bee: H, Group 4A. Do not apply more than a total of 10.5 fl oz/A per season.

gamma-cyhalothrin (Declare*): 0.77 to 1.28 fl oz/A; PHI 14 days, REI 24h, Bee: H, Group 3A.

Isaria fumosorosea Apopka Strain 97 (PFR-97 20% WDGOG): 1 to 2 lbs/A; PHI 0d, REI 4h, Bee: M, Group M.

lambda-cyhalothrin (Warrior* II): 0.96 to 1.6 fl oz/A; PHI 14d, REI 24h, Bee: H, Group 3A.

permethrin (Pounce* 25WP): 6.4 to 12.8 fl oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.

pyrethrins (Pyganic EC5.0IIOG): 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. Do not make more than 2 consecutive applications of Group 5 insecticides. Do not make more than 5 applications per year per crop.

Bulb Mites

Two genera of mites are known to infect species of Allium - a dry bulb mite, Aceria tulipae, and species in the genus Rhizoglyphus. Mites can survive in soil on decaying vegetation. Infected seed may fail to germinate. Plants grown from infected seed may lack vigor and produce stunted, deformed leaves. Plants may outgrow the damage if the infestation is not heavy, but mites may increase in number over the growing season and will remain in the harvested garlic. They are particularly troublesome in storage, causing desiccation and creating wounds that allow for entry of secondary pathogens.

Bulb mites are favored by mechanical injury, disease, cool soil temperatures, and soils with high organic matter content. Avoid adding manure and use fallow periods to eliminate crop residue. In smaller plantings, removing culls from the field immediately after harvest will reduce overwintering populations. Dark plastic mulch will increase soil temperatures and control mites. Plant clean seed and rotate out of Alliums for at least four years after an infestation. Avoid planting Allium crops directly after brassicas, corn, grain, or grass cover crops.

Onion Maggot (Delia antiqua)

For more information on this pest and for cultural and biological controls, see onion maggot in the Onion section.

diazinon (Diazinon* AG500): 2 to 4 qt/A; REI 3d, Bee: H, Group 1B. Broadcast and incorporate just before planting. Will not control organophosphate-resistant onion maggots. DO NOT make more than one application per year.

Onion Thrips (Thrips tabaci)

Thrips are favored by hot, dry weather. Thrips typically feed under leaf folds and in protected inner leaves, although when populations are high they may feed on exposed leaf surfaces. This causes white scars on leaves that can reduce plant growth when severe, as well as provide entry points for foliar diseases. In severe infestations, the field may appear silvery in color. Both adults and nymphs cause damage. 

Heavy rain or overhead irrigation can lower populations quickly. Lacewing larvae, pirate bugs, and predatory thrips are important natural enemies. Reduce populations by cleaning up crop residue after harvest to limit overwintering sites. Do not plant garlic near other Allium crops or alfalfa, clover, cucurbits, or brassicas, as these can harbor large populations of thrips that can migrate to garlic when these crops are cut or harvested. The most common controls for leek and garlic diseases include the use of disease-resistant cultivars and pathogen-free seed and bulbs, and cultural practices such as crop rotation and crop residue management that restrict the pathogens.

Begin applications when damage is first noticed. Repeat applications at 7- to 10-day intervals. 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. See onion thrips in the Onion section for more information.

acetamiprid (Assail 30 SG): 5 to 8 oz/A; PHI 7d, REI 12h, Bee: M, Group 4A.

Beauveria bassiana (Mycotrol ESOOG): 0.25 qt to 1 qt/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.

Burkholderia spp. strain A396 cells (Venerate XCOG): 1 to 8 qt/A; PHI 0d, REI 4h, Bee: MGroup UN. Suppression only.

Chenopodium extract (Requiem EC): 1.5 to 3 qts/A; PHI 0d, REI 4h, Bee: L, Group UN. Begin application as soon as thrips are seen. Thoroughly cover foliage.

Chromobacterium subtsugae strain PRAA4-1 (GrandevoOG): 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.

deltamethrin (Delta Gold*): 1.5 to 2.4 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.

dinotefuran (Venom): 3 to 4 fl oz/A foliar, 5 to 6 fl oz/A soil; PHI 1d foliar, 21d soil, REI 4h, Bee: H, Group 4A.

gamma-cyhalothrin (Declare*): 1.02 to 1.54 oz/A; PHI 14d, REI 24h, Bee: H, Group 3A.

imidacloprid (Admire Pro): 14 oz/A; PHI 21d, REI 12h, Bee: H, Group 4A. Soil applications only.

kaolin (Surround WPOG): 25 to 50 lb/A or 0.25 to 0.5 lb/gal; PHI 0d, REI 4h, Bee: L. Suppression/repellence only. Good coverage into plant crown is essential. Generally compatible as a tank mix with other insecticides.

lambda-cyhalothrin (Warrior* II): 1.28 to 1.92 oz/A; PHI 14d, REI 24h, Bee: H, Group 3A.

malathion (Malathion 57 EC): 1.5 to 2 pt/A; PHI 3d, REI 24h, Bee: H, Group 1B.

permethrin (Pounce* 25WP): 9.6 to 12.8 oz/A; PHI 1d, REI 12h, Bee: H, Group 3A.

pyrethrin (PyGanic EC5.0OG): 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.

spinosad (Entrust SCOG): 4 to 8 oz/A; PHI 1d, REI 4h, Bee: M, Group 5. Suppression only. Use adjuvant for better control.

spinetoram (Radiant SC): 6 to 10 oz/A; PHI 1d, REI 4h, Bee: M, Group 5. Thorough coverage is essential. Efficacy improves with the addition of an adjuvant.

spirotetramat (Movento): 5 oz/A; PHI 3d, 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.

zeta-cypermethrin (Mustang*): 3.2 to 4.3 oz/A; PHI 7d, REI 12h, Bee: H, Group 3A.