Doug Harp, a graphic designer friend, first alerted me to
soap as an effective all-purpose pesticide when he used Dr.
Bronner’s Liquid Peppermint Pure-Castile Soap diluted with
water to kill the gypsy moths that had infested his apple
trees. We were working on a project together, and I’d get
faxes updating me on his kill rate (this was back before e-mail),
which, much to his delight, was excellent! Impressed, I made
a mental note to look into insecticidal soaps, which I have
Soap has been used for centuries as an all-purpose pesticide.
It disrupts insects’ cell membranes, and kills pests by
dehydration. The key is not to use too much soap, or you’ll
also kill the vegetation near the pests. If you follow the
proportions of soap to water in the Soap Spray recipe, below,
the vegetation should be fine.
Note: Buy a liquid soap and not a detergent. Health food
stores have liquid soaps, such as Dr. Bronner’s Pure-Castile
Insecticidal Soap Spray
1 to 2 tablespoons liquid soap
1 quart water
Combine ingredients in a bucket, mix, then transfer to a spray
bottle as needed.
All-Purpose Pesticide Soap Spray
Strong smelling roots and spices such as garlic, onions,
horseradish, ginger, rhubarb leaves, cayenne and other hot
peppers, are all known to repel insects.
A handful of roots and spices
Enough boiling water to cover
Soap Spray (recipe, above)
Add the roots and spices to the bottom of a mason jar. Cover
with the boiling water, screw on the top, and let set overnight.
Strain, and add to the Soap Spray. Note that this will rot,
so use it all up or freeze leftovers for another time.
Variation: Garlic Spray
Use 1 to 2 heads garlic. Deer and rabbits hate the smell