Insecticidal Soap

Marijuana Horticulture

by Jorge Cervantes

Ingredients – Mild contact insecticides made from fatty acids of animals and plants. A variety of soaps are available in potassium-salt based liquid concentrates. Soft soaps such as Ivory liquid dish soap, Castille soap, and Murphy’s Oil sap are biodegradable and kill insects in a similar manner to commercial insecticidal soaps, but they are not as potent or effective.

Controls- Controls soft bodied insects such as aphids and mealy bugs, spider mites, thrips, and whiteflies by penetrating and clogging body membranes.

Caution – Do not use detergent soaps because they may be caustic.

Mixing – Add a few capfuls of soap to a quart of water to make a spray. Ivory or Castille soap can also be used as a spreader-sticker to mix with other sprays. The soaps help the spray stick to the foliage better.

Application – Spray at the first appearance of insect pests. Follow directions on commercial preparations. Spray homemade mixes every four to five days.

Persistence – Soft soaps will last only for about a day before dissipating.

Forms – Liquid.

Toxicity – These saps will last only for about a day before dissipating.

Safety – Wear a mask and gloves.