Homemade Insecticidal Soap Spray

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
since done.

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
Soaps.

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.

INGREDIENTS
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
of garlic.

Read more: Nature, Natural Pest Control

By Annie B. Bond

Disclaimer: The views expressed above are solely those of the author and may not reflect those of
Care2, Inc., its employees or advertisers.

KS G.

5:34AM PDT on Jul 18, 2011

Thanks for the article.

send a green star

Karen A.

8:31AM PDT on Jul 20, 2010

Pure liquid soap? Is this only available at a health food store? Earwigs are eating holes in everything I have this year & moths too. The weather has been in the 90's & I've watered more often, could this be why. Also, huge carpenter ants are eating my hostas, I'm thinking it's due to the heat, but I'm just an every day gardener-

mr C.

1:30PM PDT on Jul 14, 2010

that works very well. been using that for some time.

Deborah C.

12:51PM PDT on Jul 10, 2010

Very interesting. Especially as I have just been reading the thread on the top 10 countries with the worse environmental record. The use of pesticides was one of the major problems for the US. Would be great to see more eco friendly solutions- although I do appreciate that commercial crops are a slightly different ball game.

Julie F.

8:38AM PDT on Jul 4, 2010

Wished I had seen this earlier!

Josh K.

8:22AM PDT on May 26, 2010

When the directions say "do not use too much soap" Take it seriously. I just killed a quarter of an acre of organic heirloom crops using this spray. Be very cautious of the ratio and test it on every planet as some seem to be extremely sensitive to it. My plants were withering within hours and by the next day half were totally gone(only stems left) while others had browning leaves.

Donna B.

11:20AM PST on Feb 19, 2010

Thanks, good information.

Graham B.

1:52AM PST on Nov 12, 2009

I agree with so many answers to peoples questions, but I have one which I find it hard to find an answer.
How do you get rid of sparrows from invading the property keeping native birds away and spoiling the bird bath water?
Look forward to an answer soon,

Graham

Jack W.

8:44AM PDT on Aug 18, 2009

I used this recipe (2 tablespoons liquid soap to 1 qt or water) to rid my young weeping willow of aphids. This resulted in serious damage to the tree. I then checked other recipies on the Internet and see that most recommend 2 tablespoons per gallon or 2+ teaspoons per quart.

Julia B.

1:44PM PDT on Jul 23, 2009

Is this a good soap solution to spray my indoor plants? (to kill potential mites, etc. on my tropical plants...etc.