Leaves of Hollyhocks Discolored with Holes
I've heard there is an old-fashioned remedy for the holes and discoloration that hollyhocks get. Do you know what it is or have any other tips to offer?
The unsightly leaves are caused by sawflies, caterpillar-like insects, eating holes and rust, a fungal disease, discoloring the leaves. Reduce disease problems by growing hollyhocks in full sun with good air circulation. Remove nearby mallow weeds that are also susceptible and can increase the risk of the disease. A thorough fall clean up and good sanitation throughout the season may help keep this disease under control. Fortunately neither the insect nor the disease kill the plant just reduce its beauty. Try masking the unsightly foliage with nearby plants. I use daylilies, ornamental grasses and coneflowers in front of hollyhocks to hide the pest damaged leaves. This is less work for you and kinder to the environment. Insecticides labeled for sawflies and fungicides labeled for controlling rust hollyhocks can provide relief. A relatively new plant derived pesticide, Neem, is effective at controlling both the sawflies and the rust disease. Select a formulation designed for both purposes and labeled for use on hollyhocks. And as always read and follow all label directions carefully.