Some of the best, effective, yet safest, pesticides and fungicides for organic garden use can be made without using any dangerous chemicals. The best way to control harmful pests and insects is to design your total garden landscape and annual gardening strategy to incorporate continuous companion planting ideas and various intense gardening and biodiversity concepts in order to increase beneficial insect and animal populations to control the harm animals and insect populations. Intensive organic mulching through your garden landscape also controls many pests. Some advanced organic gardeners don't even use any natural pesticides or fungicides, because their soil structure and garden techniques encourage massive populations of beneficials.
However, there are exceptions where a few ideas are needed to control pests. Here is a simple list of classic organic and natural concepts:

1. Companion planting and intense gardening - you can plant certain plants close together to help fight diseases, control pests, or even improve the soil for its neigboring plants' health.
2. Garlic, onions - all alliums are great for killing soft body insects. Flying insects can be paralyzed by direct hits. Also a great fungicide. Best if crushed or liquified in a vegetable oil tea. Use several cloves of garlic per gallon of water.
3. Hot peppers - fresh or powder is great for repelling rabbits and other pests. Many soft body insects can be killed by its acidic "burning" effect. Best when mixed with garlic sprays applications.
4. Canola oil, vegetable oils - mineral oils work also, but they are made from petroleum products. Oil sprays suffocate soft body insects. Don't use too much on sensitive plants. May burn leaves. Don't use no more than 1 cup of oil per gallon of water.
5. Alcohol - rubbing alcohol is good but it is made from petroleum products. Drinking alcohols are made from plants. Using only a few tblsp per gallon of water will kill many soft body insects. Too much alcohol in water will produce a super herbicide.
6. Apple Cider Vinegar - Use 1-2 tbls per gallon of water for a mild fungicide or acidic liquid fertilizer. Like alcohol can be a natural herbicide if too much is used in tea. Most white vinegars are made from petroleum products. Apple cider vinegar can contain up to 30 trace elements.
7. Corn meal - Use as a topdressing or in a tea for fungal control.
8. Compost teas - This multi-purpose fluid can contain beneficial microbes and soluble nutrients that can be a mild fungicide and disease controller.
9. Ground cloves - great repellant and can kill flying insects. Use several tblsp per gallon of water.
10. Japanese beetles - these pests are best controlled by killing their larva during the winter and early spring seasons with mild topsoil tilling, or using milky spore or beneficial nematode soil applications. During the warm season, the best way to control them is with traps. Simple inexpensive traps can be made by placing several small open milk jugs, cans, or buckets all over your garden. Inside the cans place some rotten fruit or fruit cocktail in 1/2 can of water with 1-2 tbls of liquid soap and 1-2 tblsp of canola oil. You can also add dry molasses or liquid molasses for extra microbial power in the soapy tea mixture to attract and kill them. Also planting a border planting of buckwheat will attract these pests away from your crops.
11. Diatomeous earth - this natural powdery substance will poke insect bodies and dehydrate many soft body soil organisms, but not earthworms. It can kill bees if direct contact of a spray mixture. This can be used on the soil or sprayed on the plant with soapy water. Unlike most natural pesticides, D.E. can stay in the soil working for decades.
12. Neem oil - like vegetable oil sprays, it suffocates insects. However, neem goes the extra step of destroying soft body insects' ability to reproduce and makes them starve by removing their appetites.
13. Liquid soaps - Only use natural soaps or Murphy oil soap or mild liquid dishwashing soaps like Ivory. Soap help make teas stick better to plants and pests, and they also paralyze many insects in direct contact. Use no more than 1-2 cups of soap per gallon of water. Do not use much on flowering fruit or vegetable plants. Can hinder fruit production.
14. Citrus acid and molasses - repels and kills fire ants and similar pests. Mix 1-2 cups per gallon of soapy water. Hot boiling water mixed with garlic products, poured over the fire ant mounds will also kill the queens. You can produce citrus acid from crushing whole oranges or lemons into a tea.
15. Tobacco products - this is definitely a classic natural pesticide, but most organic gardeners today stay away from it. It may kill beneficials too if abused. It can cause diseases on tomatoes if not properly used. Most modern pro-tobacco pesticidal tea experts suggest to brew a tobacco tea no more than 30 minutes, to be safe enough to not harm beneficials like bees and ladybugs. You can mix in a liquid soap as a spreader-sticker. NOTE: Do not use tobacco teas on nightshade family crops. Also recent research has proven that the available nicotine produced in a tobacco tea is not the same stuff as nicotine sulfate. It is much safer than nicotine sulfate or rotenene. Just one drop of pure nicotine sulfate on your skin can may you sick. Homemade tobacco teas have great knock down power for tough pests like Japanese beetles. Chewing tobaccos are the most safest, natural forms for these homemade tobacco teas.
16. Bleaches and Peroxide - great fungicides. However, most commerical bleaches are not natural. Use 1-2 tblsp per gallon of water.
17. Dolomitic Limestome, Hydrated Lime, Bone Meal, Egg Shells - sprinkle a little lime or crushed egg shells around soil areas where snails and slugs live. Most high calcium carbonate products will work. Also a light dusting of lime on plants acts as a fungal control. Egg shells also have the extra benefit of discouraging snails and slugs because of its rough edges.

You can mix together several of the above materials in a special compost tea brew and it will become even more powerful against pests. Be careful not to abuse these brews, because they may harm beneficials if not used properly.
Happy Gardening!

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