Q. I have an established planting of peony bushes that are attacked by blight every year. What is the best way to prevent this disease from recurring?
A. Peonies can suffer from several fungal blight problems, including botrytis and bud blast. The leaves and stems develop dark spots or streaks, and the flower buds turn black and never open. These fungal problems favor damp, crowded conditions where there is inadequate sun and air circulation. Always plant peonies in full sun in soil with good drainage. If the fungus persists, they will need to be sprayed annually with an approved fungicide as soon as the shoots are 2 to 4 inches tall in early spring. Repeat the spraying as per label directions. Infected foliage must be removed from the garden bed and should not be composted.