Insecticidal Soap - Homemade

You’ve probably heard that one of the newest organic insecticides is “insecticidal soap”. Several manufacturers make insecticidal soaps and they can be found at most garden centers. But you have also probably had a neighbor recommend that you just mix up some liquid household soap with water and make your own home-made, cheaper, insect poison. Is this a good idea?

In fact, a home-made insecticidal soap could burn the leaves of the plants you spray it on. Household soaps are made by reacting lye with one of several plant oils or animal fat. You have no way of knowing which oil or fat was used to make the liquid soap. Some of these soaps will harm plant tissue just like they harm insects - by cutting the waxy coating on the organism’s skin and causing it to dry out. Our skin can’t tell the difference between the soap products - but our plants sure can!

The manufactured insecticidal soaps are tested thoroughly to make sure they do not harm the plants on which you spray them. You could be a classic case of “Penny wise and pound foolish” to mix up and use home-made insecticidal soap. Use the store-bought brands for safety’s sake.