Hydrangea Leaves And Flowers Drying And Turning Brown

Question From: C. Saunders - Plymouth, Michigan, United States
Q: Hi -- Enjoyed your columns, thank you. My question: I have 2 Anna Bella hydrangeas - just put in last fall. Both did well when suddenly, one started getting brown drying on leaves and flowers. That is the one I often pour my extra tea on (about a week - heard it was good for it). Can you tell me what to do and when do I trim, and how do I trim for the winter. Thanks much, Camille Saunders

A: Camille, Flowers will dry out as part of the aging process, but if they do so prematurely - as you have compared the flowers on the two shrubs, there is a problem. If any herbicides have been sprayed in the landscape, drift of the chemical may have hit the shrub. Lack of water will cause leaf and flower death but there should be telltale wilting. Animals tunneling amongst the roots may be the problem. Anthracnose is another possibility. However, before the leaves turn brown they will develop dark spots, often surrounded with a yellow halo. If this is the case remove the infected branches and clean up any dead foliage in the ground. Be sure to clean your pruners with rubbing alcohol. The plant can be treated with a fungicide. Phytophthora root rot is another possibility. It's caused by too much water or drought, along with poor draining soil. It may have come with the shrub as this disease is most often seen in green house plantings. There is no treatment, so if it continues to worsen, I would remove it. Do not plant another hydrangea in that spot. The tea is good for hydrangeas as it increases the pH of the soil. The leaves are also beneficial. Hydrangeas do not need pruning unless they need to be thinned or dead branches require removing or they need to be reduced in size. Crossing branches should also be pruned out. This is best done in late winter or early spring. Pruning before the shrubs go dormant will stimulate new growth that will suffer winter kill. Remove flowers by cutting them at the base of the cluster, above the first set of leaves. Cutting the shrubs back hard results in weak stems that tend to droop when in flower. Best And Happy Yardening, Nancy