Pest Management Guidelines

Several options may be used to help reduce insect pests in home gardens. These include the use of pest-resistant varieties, mechanical controls such as row covers or hand picking pests, and cultural practices including roguing on infested plants. Some are more practical than others, and success will depend in part on your willingness to work at them. Integrated pest management (IPM), an approach that uses all pest control options, is recommended. The goal of IPM is to reduce risks to the environment and human health.

One of the most important strategies in dealing with insects is to learn about their habitat, behavior, life cycle, what they feed on, and whether they are actually pests. This information will help you decide what to do. Most insects found in the garden are not pests, and some are beneficial. See Part I, Chapter 12, for cultural recommendations and troubleshooting in the home garden.

Another important aspect of IPM is deciding just how many pests or how much damage can be tolerated. For example, feeding damage to wrapper leaves on cabbage is tolerable because the leaves are discarded anyway. It is not necessary to eliminate all pests; in fact, having a few present allows natural enemies to feed and reproduce and maintaing some balance between beneficial and harmful insects. Before taking a control action, be sure it is really necessary.

Pesticides may also be used as part of the pest management program but should be used only when the other options have not proven effective. Be sure to use only the amount needed and to treat only the plants that need treating. Spot treatments are effective and may be practical for home gardens. See Table 16 for pesticide options and Tables 2 and 3 for toxicity information.

The use of biorational pesticides such as Bacillus thuringiensis (Bt), a toxin produced by bacteria that kill caterpillars, is strongly encouraged. These products affect only caterpillar pests, leaving beneficial insects unharmed. Traditional chemical pesticides will control the pests but also eliminate beneficial insects that naturally help to suppress pests. Insecticidal soaps are also an alternative to some chemical pesticides and may be useful for certain pests, especially aphids, in the home garden. Diatomaceous earth, a desiccant, is sometimes used to control insects, slugs, and snails. Once it gets wet and compacted, however, it loses its effectiveness.

Before using any pesticide, check the label. Both the crop you wish to treat and the pest you are treating for must be listed on the label. If not, do not use the pesticide. Also make sure to read the label to determine how long you need to wait before harvest. Harvesting treated vegetables too soon after a pesticide application may result in excessive residue being present when consumed.

Even if a pesticide is botanical in origin it may be toxic. Some botanical insecticides are more toxic than some of the commonly available synthetic chemicals.

No matter which methods you choose, keep a record of what you did and whether it was successful. Such a record should be a great help in the future when you are faced with similar pest management decisions.

Purchase Treated Seed

Seed may come pretreated with a dusting of a fungicide, or you may dust the seed with a fungicide such as captan or thiram according to the directions on the label. This coating will help prevent the seed from rotting in the soil before germination and can help protect the emerging seedling from damping-off. If seed rot or damping-off has been a problem in your garden, treating the seed with a fungicide will help.

Table 16. Vegetable pest management
Plant	Pest/Disease	Some recommended pesticides for management
Asparagus	Asparagus beetles (common and spotted) Common asparagus beetle	Carbaryl, malathion, or rotenone: apply one to three times a minimum of three days apart as needed. Do not harvest until one day after treatment. Do not repeat applications within three days.
Beans Bean common mosaic virus, strains BV‑1 and NY 15 Bean leaves showing mosaic and distortion caused by common mosaic virus		Manage insect vectors (see insect entries).
	Botrytis gray mold	Apply chitosan, chorothalonil (7 DTH [Days to Harvest]), or thiophanate-methyl (14DTH) per label directions.
	Rust	Apply chlorothalonil (7DTH), neem oil, or sulfur according to label directions.
	Aphids	Use insecticidal soap, oil, pyrethrins, or malathion.
	Leafhoppers	Use insecticidal soap, carbaryl, or malathion: apply when leafhoppers are present. Wait one day before harvesting if using malathion or carbaryl.
	Mexican bean beetle and Japanese beetle	Apply carbaryl, malathion, neem (repels beetle), or Rotenone as needed. Wait one day before harvesting.
	Seedcorn maggot	Purchase insecticide-treated seed. Wear gloves when planting.
	Spider mites (two-spotted)	Use insecticidal soap.
Beet	Cercospora leaf spot	If severe, apply Basicop, or copper salts of fatty & rosin acids according to label directions.
	Leafminer	Commercial beets are not sprayed for leafminer; spray only if leaves intended for consumption are infested. Use malathion: spray when mines appear and at seven-day intervals as needed. Wait seven days to harvest.
Cabbage, cauliflower, broccoli, Brussels sprouts, and other cole crops	Clubroot *(Plasmodiophora brassicae)* Clubroot of cabbage	Set transplants with Terraclor (PCNB) 75WP according to label directions.
Cabbage root maggot	Cabbage aphids	Use insecticidal soap, oil, pyrethrins, or malathion: spray when infestations are excessive and weekly as needed. If using malathion, wait seven days before harvest.
Cabbage root maggot	Cabbage root maggot	Entomophagous nematodes: apply as directed on label.
	Cabbageworms Cabbageworms	Use Bt, insecticidal soap, spinosad, carbaryl, malathion, or rotenone: spray or dust as needed. Wait three days before harvesting.
	Flea beetles Flea beetles	Use carbaryl: spray or dust as needed. Wait three days before harvesting.
Carrot and parsnip	Cercospora (early blight)	Apply chlorothalonil, Kop-R-Spray, or Camelot according to label directions.
	Alternaria (late blight)	Apply chlorothalonil or Gordon’s Maneb according to label directions if needed. Wait 14 days before harvesting if using chlorothalonil.
	Carrot rust fly	No pesticides registered for home garden control.
	Carrot weevil	Entomophagous nematodes: apply as directed on label.
	Leafhopper	Spray with carbaryl as needed.
Corn	Helminthosporium leaf blight	Apply chlorothalonil or Gordon’s Maneb according to label directions as needed. Wait 14 days before harvesting if using chlorothalonil.
Rust Closeup of rust postules on a corn leaf		Choose resistant or tolerant varieties. For se bicolor types try: Temptation, Sensor, or Lancelot. Before tassel emergence, apply chlorothalonil or Heritage and repeat if disease is severe and weather is warm during the day and cool at night. Wait 7 days before harvesting if using Heritage, 14 days if using chlorothalonil.
	Smut	Pick and remove galls before they break open. Plant resistant or tolerant varieties: Sweet Rhythm, Wizard, Sweet Symphony, Lancelot or Silverado.
European corn borer, corn earworm European corn borer		Bt, spinosad, or carbaryl: spray or dust foliage and silks. Apply when tassels begin to emerge and thereafter as needed. Release Trichogramma ostriniae wasps for control of corn borer.
	Seedcorn maggot	Use insecticide-treated seed; wear gloves when planting.
Cucumber	Cucumber Mosaic Virus	Manage aphids that spread the virus (see aphid entry below).
	Downy mildew	Apply chitosan, chlorothalonil, Kop-R-Spray, maneb, basic cupric sulfate, or Camelot according to label directions.
	Gummy stem blight and black rot	Apply chlorothalonil, thiophanate-methyl, Gordon’s Maneb, Heritage, or Bonide Copper Spray/Dust according to label directions.
	Powdery mildew	Apply chitosan, chlorothalonil, neem oil, potassium bicarbonate, thiophanate-methyl, Kop-R-Spray, Heritage, Bonide Copper Spray/Dust, Sunspray Ultra-fine oil, or Camelot according to label directions; or select PMR (powdery mildew–resistant) varieties like Marketmore 76 and 78, Dasher II, Turbo, or Meteor
Striped cucumber beetle	Aphids	Use insecticidal soap, oil, or malathion: spray as needed when vines are dry. When using malathion wait one day before harvesting.
	Squash vine borer	See Squash. Destroy crop residues after harvest.
	Striped or spotted cucumber beetles	Use carbaryl: spray or dust when beetles are excessive and weekly as needed. Control of beetles is important to prevent bacterial wilt in cucumbers but less important with other vine crops.
Eggplant	Aphids	Use insecticidal soap or malathion as needed.

Pest Management Guidelines A Cornell Cooperative Extension Publication	New York Pest Management Guidelines
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