Marijuana Horticulture: The Indoor/Outdoor Medical Grower's Bible

these substances to edible plants

    NOTE: This list is not all-inclusive. The basic rule is to not use systemic products.
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    Use only contact sprays that are approved for edible plants. Avoid spraying seedlings and tender unrooted cuttings. Wait until cuttings are rooted and seedlings are at least a month old before spraying.

Sprays and Traps
    I do not recommend using chemical fungicides, fungistats, insecticides, or miticides on plants that are destined for human consumption. Most contact sprays that do not enter the plant system are approved for edible fruits and vegetables. However, there are numerous ways to control fungi, diseases, and pests without resorting to chemicals. On the previous page is a chart of common chemicals with their trade names and the insects they control.
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EPA pesticide acute toxicity classification:

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Spreader-Sticker for Pesticides
    Spreader-stickers improve and promote wetting and increase sticking and absorption through foliage. Spreader-sticker products increase effectiveness of fertilizers, fungicides, insecticides, etc. They are especially important to use when plants develop a waxy coating of resin. Spreader-stickers also impair insects’ respiration mechanisms and function as pesticides. One of my favorite spreader-stickers is Coco-Wet from Spray-N-Grow.
Abamectin
    Ingredients: Abamectin derivatives include emamectin and milbemectin. Does not bioaccumulate. Used extensively on hops; abamectin is not truly systemic. It is absorbed from the exterior of foliage to other leaf parts, especially young leaves, in the process of translaminar activity.
    Controls: Russet and spider mites, fire ants, leafminers, and nematodes.
    Mixing: Dilute in water. Mix 0.25 teaspoon (0.125 cl) per gallon (3.8 L). Use a wetting agent.
    Application: Spray. Works best when temperature is above 70°F (21 °C). Repeat applications every seven to ten days.
    Persistence: One day.
    Forms: Liquid.
    Toxicity: Toxic to mammals, fish, and honeybees in high concentrations. Sucking insects are subject to control while beneficials are not hurt.
    Safety: Wear gloves, mask, and safety glasses.
Bacillus thuringiensis (Bt) and Bacillus species
    Ingredients: Bacillus thuringiensis (Bt) is the best known of several bacteria that are fatal to caterpillars, larvae, and maggots.
    Caterpillars, larvae, and maggots all eat Bt bacteria, which can be applied as a spray, dust, or granules. Inject liquid Bt into stalks to kill borers. Shortly after they ingest it, their appetite is ruined, and they stop eating. Within a few days they shrivel up and die; cabbage loopers, cabbageworms, corn earworms, cutworms, gypsy moth larvae, and hornworms are controlled. Commercial Bt products do not reproduce withininsect bodies, so several applications may be necessary to control an infestation. Microbial Bt bacteria are nontoxic to animals (humans), beneficial insects, and plants; however, some people do develop an allergic reaction. Commercial Bt products do not contain living Bt bacteria, but the Bt toxin is extremely perishable. Keep within prescribed temperature range, and apply according to the directions. Most effective on young caterpillars, larvae, and maggots, so apply as soon as they are spotted.
    Get the most out of Bt applications by adding a UV inhibitor, spreader-sticker, and a feeding stimulant such as Entice®, Konsume® or Pheast®. Bt is completely broken down by UV light in one to three days.
    B. thuringiensis var. kurstaki ( Btk )– introduced on the market in the early 1960s–is the most popular Bt. Toxic to many moth and caterpillar larvae including most of the species that feed on flowers and vegetables. Sold under many trade names DiPel®, BioBit®, Javelin®, etc., Btk is also available in a microencapsulated form, M-Trak®, Mattch®, etc. The encapsulation extends the effective life on foliage to more than a week.
    B. thuringiensis var. aizawai (Bta) is effective against hard-to-kill budworms, borers, army-worms and pests that have built up a resistance to Btk.
    B. thuringiensis var. israelensis (Bt-i) is effective against the larvae of mosquitoes, black flies, and fungus gnats. Look for Gnatrol®, Vectobac®, and Bacrimos®. All are lethal to larvae. Adults do not feed on plants and are not affected. Fungus gnats can cause root problems including rot. Use Bti to get rid of them as soon as they are identified.
    B. thuringiensis var. morrisoni is a new strain of Bt under development for insect