On Sunday I noticed white powdery mildew on my zucchini leaves. This is bad, I thought, really bad. And it was. I did a little research, and it seems that there's no way to reverse the mildew.
|photo from portkellsnursery.com|
All of the leaves showing signs of mildew have to be removed. You can see from the photo that it works it's way down the stems as well. You can't reverse it, but you can halt it in it's tracks. I found a recipe for a non-chemical treatment. It was one gallon of water, and a tablespoon each of dish detergent, vegetable oil, and baking soda. The plants get a daily light spray of this mixture while they are infected, and weekly when they are not. I will have to report back as to how they are doing.
Plants with large leaves are succeptable to powdery mildew. In my garden that means squash (zucchini, crookneck, and spaghetti) and also cucumbers (lemon and burpless). Of course, they are planted right next to each other (of course they are!) so it just spread down the row like crazy. The top of these plants are much less infected than the bottoms, where the leaves are denser. It's tragic. I hope to be able to get a handle on this fungal infection before I lose my whole plant to it. Wish me luck.
There is some discussion about the milk based spray vs. the baking soda and soap based spray. The guy and I didn't think that spraying milk, which would spoil, on the plant seemed like a good idea. I found a day by day comparison (in someone else's garden, thankfully), and once reading it, my mind was made up. Here's the blog: http://voices.yahoo.com/get-rid-white-fuzzy-spots-zucchini-plant-leaves-8762103.html
That's it for now... updates later.
Green thumb out.