Rosemary, a D&B Garden Show listener, asked about how to make soap spray and how to use it.


Q: I’m Rosemary from Nampa that talked to you about zucchini and squash bugs this morning.

Thanks again for your help. But then I got a phone call and missed some of your program. I hate when that happens. When I got back to it, you were talking to some man about spraying his vegetables with soapy water. What was that supposed to kill?

I was wondering if I could do that on my zucchini plants when I see tiny juvenile squash bugs.

I don’t like to use any commercial sprays on food I’m going to eat. I was so sorry I missed that conversation.


A: Here’s the deal with soap and bugs….

Consider making your own soap spray. It will save you some money and works as well as a pre-made product. However, you can’t discount ease of purchase. When making your own soap spray, use a pure soap. I use Fels Naptha, a bar soap. You can also look for Castille or Ivory. I find the Fels Naptha in the grocery store by the pre-wash spray. It’s wrapped in paper and looks old fashioned. I grate it on the small part of my cheese grater and it basically makes a powder. Here’s the recipe;

Soap Spray

  • 2-3 TBS of the soap
  • 1 Gallon of water
  • 1TBS rubbing alcohol (it cuts down on the foaming of the soap)

This soap spray must GET ON the insect. It’s the fatty acid in the soap that breaks down the waxy coating (the cuticle) of the insect causing them to die. It will work on soft-bodied insects like aphids, mites, etc. I have not had good luck spraying this on adult squash bugs but the immature insects are more affected. Don’t forget to get the bronze looking egg clusters off the underside of the leaves.

Next year try planting nasturtiums in with the squash plants. They are said to repel the squash bug. If nothing else they look really pretty and attract pollinators.

Thanks for listening to the show and thanks for the question. Good luck with your squash!

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes:

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>