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White spots on my garden plants #798516

Asked June 29, 2022, 10:54 AM EDT

My plants have some sort of white spot disease. Three of the butterfly bushes I bought last all succumbed to this, didn't even bloom this year, and had to be thrown out. I have one left and it has this problem too. Now I see my dahlia has this problem, also my lambs ear, mint, some of the obedient plant, and the rosemary. Any ideas? Thank you!

Frederick County Maryland

Expert Response

Hi and thanks for reaching us

It's no joy when you expect to have lush green plants and to find them discolored. Insects also like lush green plants that are stressed; which make them delicious for them.

What do you see is what we call stipplings. Someone or many suck out the chlorophyll, the green color, one leaf cell at a time. If you look under the leaves, you can see them. they can be, for example, the size of a dot in a newspaper (mites), be white (like a whitefly), have transparent wings (lacebugs) or be green with edge-like wings (leafhooper). It's a fascinating word to discover.

To control insects, you can attract beneficial insects, spray the undersides of the leaves with water, or use insecticidal soap or oil to spray the underside of the leaves. Before using insecticides, you should inspect the underside of the leaves  and make sure that there are no beneficial insects such as, for example, wasps, ladybug larvae (resembling alligators), tiny prying mantises or insects are present.

Good luck,


-Nick Replied June 30, 2022, 9:20 AM EDT

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