Organic pesticides are pesticides made from naturally occurring substances or self-made mixtures made from organic soaps and/or ethanol.
Introduction
Organic pesticides can allow farmers to control pest and diseases in plants without resorting to conventional pesticides. This does not necessarily mean that they are safer to use. Organic presticides can be as damaging to the fauna/flora in the environment as chemical pesticides [1]. However, in comparison to chemical pesticides, they can be much more easily decomposed by the environment.
This page lists the organic pesticides you can make locally, and discusses against which pest/disease it is effective. The recipes themselves can be found at organic pesticide recipes.
Use pest-specific pesticides
The key to using pesticides appropriately is to use pesticides that are (as much as possible) is to know exactly what the problem or pest/disease is that is causing problems. Some problems may not be pests/diseases at all, rather nutrient deficiencies. If it is a pest/disease, try to identify it before using any pesticides at all.
Here are some resources that can help you identify the problem:
- Texas Plant disease Handbook- This excellent resource has a list of common crops in Texas and commonly associated pests and diseases. Pictures included
- A guide to Natural Enemies in North America - List of predators with pictures. Useful guide but some latin may be required!!
- Household and Structural Pest Identification - Follow the key to identify common pests.
List of organic pesticides
Note: Where a plant is named as a potential pesticide, this plant the substance is derived from can often be intercropped to have the same pesticidal effect
| Organic Pesticide | Against which pests & diseases ? | Notes and academic articles |
|---|---|---|
| Ethanol | Mealy bugs | ? |
| Human/animal urine | Aphids, caterpillars | Has dual use as it acts both a fertiliser and a pesticide |
| (Wood) ash | Common insects | repellant substances as wood ash can be placed around the edge of vegetable areas to reduce pests. It is presumed that this materials is avoided by insects and small rodents |
| Baking soda, sodium bicarbonate, potassium bicarbonate | fungi, powdery mildew, rose black spot, anthracnose, downy mildew, brown patch | http://attra.ncat.org/attra-pub/bakingsoda.html |
| Black Jack seeds | Aphids, cattepillars | ? |
| Cornmeal, cornmeal solutions | yellow leaves on photinia, brown patch, algae in seedlings, leaf spots on roses | ? |
| Dead bug spray | Any insects | http://wiwi.essortment.com/homemadeorgani_renu.htm |
| Garlic, garlic solutions | Aphids, thrips, mosquitoes, onion flies, rabbits (on potatoes), other chewing and sucking insects | When using garlic on soil with thrips, it will cause the thrips to come to the surface. Once they are at the surface, fermented water/plant mix (from stinging nettle) can be used. Garlic can also be intercropped to repel similar insects |
| Chinaberry leaves | Aphids, caterpillars | ? |
| Milk, milk solutions | Mildew, blight | Abstract, Crop Science (Vol. 18, 1999, pp. 489-92) |
| Neem leaves | Aphids, Bull worm, caterpillars | Neem can have multiple functions such as for medicinal use. See Neem article |
| Paprika, hot pepper | cats, dogs, insects, bugs, snails and snails (on leaves) | often used in combination with spearmint to improve effectiveness |
| Soap, soapsuds, soap solutions | Slugs, aphids | Solutions can be sprayed on any plant leaves or used near affected plants |
| Spearmint | insects, bugs, chewing insects | often used in combination with hot pepper to improve effectiveness |
| Tobacco, nicotine, nicotine solutions | Caterpillars, aphids, many types of worms, fungus gnats, symphylids, centipedes, root lice, other underground pests | Solutions can be sprayed on any plant leaves or used near affected plants |
| Tomato leaves | common insects, blight | [1] |
To be added to list:
- Neem oil
- BT
- Confusion Lures
- Copper Sulfate
- Jojoba Oil
- Citric Acid
- Potassium Bicarbonate
- Sulfur
- Insecticidal Soap
- Paraffinic Oil
- Diatomaceous Earth
- Garlic Oil
- Spinosad
- Pyrethrum
- Kaolin Clay
- Bordeaux mixture
- silicic acid
Others
Rock meal: Seaweed calcium, basalt and lava meal have a crop protective function. They increase the acidity which impairs development of bacteria and fungi. The fine rock meals act dehydrating and damage the wax layer of many insects. By dusting or spraying, the plants are covered with a thin layer of dust. Treatment is done in the evening and it should not rain for 12 hours (maximally done for up to 2 times per month). Dosage= 250g/are.
Commercial preparations: Soap: a hot water solution with 1 to 3% (10-30g/liter) soft soap (green or brown) has a moderate working against aphids and some other insects. The insects must be properly hit with the soap solution.
Ethanol-soap mixture: ditto above but add 50 ml of ethanol per liter of water
soap spiritus: brown soap +green soap +spiritus
Sulfur: one sprays pure sulfur against several fungi (mildew and scab). Is harmless to humans and animals.
the spraying of silicic acid increases the plant defenses
cupper sulphate /cupper hydroxide /cupper oxide + Bordeaux mixture are other ecologic pesticides
Bordeaux mixture: is a mixture of copper sulphate and slaked lime. It works preventively to fungal attacks. It is a very old mixture. The copper ions on the leaf prevent the germination of the fungal spores and the calcium also increases the pH.
Pyrethrum: this plant-based insecticide is a strong neurotoxin to all cold-blooded creatures. It is virtually harmless to warm-blooded creatures however. Pyrethrum breaks down within 48 hours. Other plant-based insecticides are Koppert Rotenon and Koppert Plantschoon.
See also
- Integrated_Pest_Management
- Organic pesticide recipes
- Fertiliser - some fertilisers also work as a pesticide against some pests
External links
- ↑ http://www.bna.com/webwatch/organicpesticide.htm Organic pesticides]