Questions about pruning, fescue and disease

Published 12:00 am Saturday, May 20, 2023

The weather has been nearly perfect for work outdoors over the past few days with warm days and cooler nights. Below are a few gardening questions that may be of interest to other home gardeners.

Question: I have a large hydrangea that has dead limbs from the base. There are some green leaves emerging from the bottom, but little to none coming out on the dead stems. I’m afraid to cut them back because it may impede my blooms this summer. What should I do?

Answer: If the stems are not showing any signs of leafing out, then go ahead and cut them back to the green portion of the plant. It was a cold winter and many hydrangeas were damaged. There some cultivars that can withstand cold winter temperatures. However, many of the older “grandiflora” types are easily damaged in severe winter weather.

Question: I have an old variegated aucuba that looks really bad. One of them has a huge area of dead leaves. The adjacent one is showing a few leaves that look as if they are also dying. Can you tell me any idea what to do?

Answer: It sounds like your shrub as phytophthora root rot. It’s a very common soil born fungus that slowly kills many shrubs including azalea and rhododendron. Be sure to plant these shrubs in well drained areas and do not over water. It’s most likely too late to save the dying shrub. Go ahead and remove it. The other shrub may survive if it doesn’t have the fungus. You can also drench the soil with a systemic fungicide, but these drenches can be very expensive and time consuming.

Question: I have some forsythias that are about 10 years old. I miss pruning it after it finished blooming this year. Can I still do some light shaping pruning now?

Answer: Yes, they are starting to set their buds in a few weeks, so you have until mid-June to prune the plants back and shape them. Don’t prune them past July 1.

Question: I planted some fescue in a few bare spots in my lawn this spring. The grass is really growing, so when is the best time to cut the newly emerging fescue?

Answer: Mow the new grass as soon as it gets to a height of about 4-4 1/2 inches. The grass will be damaged if you let the grass seedlings get too tall before mowing. Mower heights for fescue should be 3 ½ to 4 inches for best growth. Make sure your mower blade is sharp and mow often. The more often you mow, the better your lawn will look.

 Darrell Blackwelder is the retired horticulture agent and director with the North Carolina Cooperative Extension Service in Rowan County. Contact him at