When should you use an organic pesticide? If and when everything else has failed. Start with homemade and work your way up to commercial if you have to.
There are three homemade sprays you can make with ordinary household products and a plastic spray bottle (which you can purchase by clicking on the link below). You will, of course, want to test them first on a few leaves to make sure it doesn’t cause any damage – if it does, it will need to be diluted further with water. Once you have found the right mix, you will need to completely coat the plant’s foliage from bottom to top, making sure you get all stems, branches, and the underside of every leaf in addition to the top side.
Garlic Pesticide – Puree a large head of garlic (skins removed) with 2 cups of water in a food processor, and pour through a fine mesh strainer. You can reserve the garlic pulp for use in cooking, and pour the liquid into the spray bottle. Add 2 or 3 drops of natural insecticidal soap, shake well, and spray your plants. Click on the Amazon.Com link below to order a natural insecticidal soap made from plants:
Hot Chile Pesticide – Puree 3 or 4 habanero or serrano chile peppers (de-stemmed) with 2 cups of water in a food processor, and pour through a fine mesh strainer. You can reserve the pepper pulp for use in cooking, and pour the liquid into the spray bottle. Make sure to protect your eyes and hands while preparing and spraying this particular pesticide, as these particular chile peppers are an extreme eye and skin irritant to humans as well as pests. You don’t want to inhale it while preparing or spraying, either, as it can cause respiratory distress, so make sure you prepare it in a well-ventilated area, and stand upwind when you spray! You do not want to spray the fruits or vegetables themselves.
Oil & Soap Pesticide – Make an emulsion of 1 cup water, 1/3 cup vegetable oil, and 1 teaspoon natural dish soap, and pour the liquid into the spray bottle. Spray your plants, shaking frequently to maintain the emulsification. This blend also acts as a fungicide.
If your only issue is fungus, you can make a fungicidal spray by mixing 1 tablespoon of baking soda and ¼ teaspoon of natural insecticidal soap with one gallon of water. The soap will help it stick to the foliage and has the added bonus of killing any pests that might happen along.