Will cleaning mildew on my house's siding with diluted Dawn detergent mixture harm nearby hollies?

Question

In front of my house, I have large holly bushes which have some bald spots. I don't want to harm them in any way.

Will overspray from diluted Dawn detergent harm them?

Answer 1

I'm not sure how Dawn specifically interacts with holly, but people mix dish soap into water (and other stuff) to spray on vegetables (to get rid of insects, powdery mildew, and such), and it doesn't seem to bother the plants terribly. I wouldn't think it would hurt your plants. It might be better to do it when the sun isn't shining, though.

Answer 2

I use bleach every year ,diluted 1:3 water, I avoid spraying plants but some over-spray must hit them and I have never seen plant damage. Although none of my hollies are near the house.

Answer 3

I use copper sulfate crystals, dissolved in water, then placed into my pressure washer mixture reservoir. I have it to be a longer lasting solution than bleach.

To update this post: The copper sulfate solution has kept my white aluminum siding perfectly clean for now over a year.