How to Make Homemade Insecticidal Soap for Plants | Today ...
To make homemade 2% insecticidal soap 5 tablespoons soap to 1 gallon of water or 1 heavy tablespoon soap to 1 quart of water. To help the solution stick a little longer, add two tablespoons of light cooking oil (such as corn, canola, olive, or safflower) per gallon of water to the mix.