I have what I think is a fungus in my garden. It has killed my squash, pumpkins, and cucumbers. I was planning on planting a cover crop once the garden is done for the season. Should I do something else? Can I fight it now or wait till next year?
Clackamas County Oregon
Thank you for your question. Although I am unable to see the fungus clearly, itbis likely powdery mildew in its advanced stages. This is a fungus with airborne spores that land on the leaves and eventually deprive the leaf of food. It is far too late in the season to do anything now except destroy (do not compost) the leaves, since the fungus can overwinter on plant tissue. Here is an Extension article about it: http://ipm.ucanr.edu/PMG/PESTNOTES/pn7406.html As for cover crops, you do not say what crops you are planting. Although powdery mildew is less prevalent in the winter, it is not unknown. If you will indicate your intended crop, we can tell you the susceptivity of the fungus. Good luck!