What is killing my lilac bush?
My parents planted two lilac bushes in partial sun over ten years ago. They have struggled and haven't bloomed fully since those first two years. They appear to be covered in a fungus -- leaves are powdery gray and the branches are covered with blue gray lichen. The branches are mostly leaf-less, with some twigs dead and others with sparse leaves here and there. What could be the problem?
Washington County Iowa lilac bushes
Lilacs have two site requirements. Lilacs need full sun. They should have at least 6 hours of direct sun each day. Lilacs also need a well-drained soil.
Powdery mildew is common on lilacs, especially when planted in partial to heavy shade.
The poor performance of the lilacs is probably due to poor site conditions (insufficient sunlight).