Our dogwoods started to show stress in July. They are now covered in a powdery mildew-like substance and the leaves are shrivelling. My local nursery told me to apply Bonide Plant Fungicide when it drops below 80 degrees. The can says to use in spring. What should I do? If I can't use this product, is there anything I can do this fall to help them out?

thanks, laura

Make sure they do not have a borer. The dogwood borer attacks at the base of the plant. It attacks stems 1 1/2 inches in diameter near the soil line. Look for exit holes almost big enough to put a pencil in them. If you have borers, prune out any stem larger than 1 inch. Cut them off between 1 and 3 inches. Powdery mildew is controlled when infection starts in the spring to avoid summer defoliation. With a late summer/early fall infection, we recommend you forget treating and instead do very good sanitation to reduce how soon and how severe it will be the next spring. Bear in mind that this disease can blow for many miles and cause infection even though you do 100% sanitation. This fall consider a light fertilization as they start to go dormant. Only fertilize if you can do it right. Too much fertilizer may burn and kill the plant or make it more prone to diseases. Too light - you might as well not feed at all.