Mildew on zucchini

Credit: Rasbak

Q: I have 3 beautiful zucchini plants and one is not as healthy as the other two. How do I cure white blotchy leaves? Also all the plants have lots of bugs. Any suggestions for insecticides?

The white blotchy leaves sounds like powdery mildew. Zucchini is very prone to mildew infection. It’s caused by several species of microscopic fungi and develops in warm, humid weather. Conway Lum, GardenWise’s plant problem and pest expert, gives some advice on dealing with mildew on our website. The article is about lilacs, but much of his advice can be applied to zucchinis, too.
Another home remedy option is using milk as a fertilizer. Check out this interesting article about the benefits of milk as an alternative method of controlling powdery mildew. It’s worth a try!
As far as the bugs on the zucchini plants, some insects are beneficial to plants, so you’ll want to identify the insects before making any moves. We caution against using pesticides and strongly suggest you never apply pesticides to food plants. There are some safer methods of dealing with insect pests that won’t harm humans, animals or the environment. For more information on beneficial bugs, visit our website. If you want to know more about non-toxic pesticide options, read this great article by GardenWise contributor Sheena Adams.