|My zucchini and yellow squash leaves are starting to show what look like blisters (similar to a sunburn before it starts to peel). The plants get sunlight from about 9 - 4. Could this be an infestation of some kind and how do I treat it.
|If the plants look healthy otherwise, it may simply be fluids escaping from the natural openings in the leaves because of hot weather; or fluids escaping through holes made by insects. As long as the plants continue to grow and produce, it's nothing to worry about. However, viruses (Cucumber mosaic virus, Papaya ringspot virus Type W, Watermelon mosaic virus 2, and Zucchini yellow mosaic virus) can cause similar symptoms. Usually the symptoms are throughout the plant rather than just on a few leaves. Some symptoms include: Young infected plants may exhibit prominent vein clearing, chlorotic spotting and a mosaic on leaves. Older plants may exhibit stunting with varying degrees of mottling, leaf blistering and malformation and vein extension along leaf borders depending on the strain of virus, age of infection and possibly other factors. Yellow squash varieties will exhibit varying degrees of fruit greening in a striped or mottled pattern, sometimes with raised yellow blisters. Green-fruited squash may lighten or mottle in color as well as blister. Fruit distortion can be severe across all squash types. There is no cure. Affected plants should be removed from the garden and squash plants should not be planted in that same garden space for several years. There are resistant summer squash varieties so if a virus is the problem, be sure to purchase resistant squash varieties next time you plant squash.|