Gardening Q&A

RICHARD NUNNALLY Q:My yard is looking dreadful. What should I do to rid the yard of the crabgrass? My guess is that I should have done a second application in early summer. Now I want to winterize and reseed and rejuvenate the fescue.

Answer: Unfortunately, there is no permanent cure for crabgrass in a fescue lawn. You're right, in cases of heavy crabgrass it is a good idea to make a second application around June 1st.

For your current crabgrass, you have two choices: You can leave it alone. It's an annual and will die on its own with the first killing frost. Or you can spray it with a grass herbicide then reseed the next weekend. In either case, consider aerating to prepare the soil for the seed and fertilizer.

If you opt to leave the existing crabgrass alone, you'll want to broadcast your seed right into it. Your new seedlings will come up through the crabgrass and once frost kills the weeds, your new grass will be already on its way.

As for next spring, be sure to mark your calendar to make your first application of pre-emergent in March and a second one around the first of June.

Q:Last spring, I seeded the bare spots under my cherry trees with a seed specifically designed for shady areas. I watered regularly and allowed the grass to grow 4 inches or so before mowing. I thought it was well established -- until we had some heavy rains and all the grass bent over and died. It was a waste of money and time. What should I do this fall to get grass to grow in my shady areas?

Answer: Spring seedings don't do very well here. They germinate fine, but the heat of summer and the competition with the tree roots are too much for cool season grasses. You should have better success by planting this area this month. In fact, you need to plant it right away so it will come up before the leaves begin to fall. Don't let your seedlings get too tall before you mow them. Those first few mowings help the plant branch out, which helps the grass plants mature. Set your mower at 2½ inches and when your grass gets to 3 inches, mow it. At some point, you may want to get your soil tested. Seeds will sprout almost anywhere, but they need certain nutrients and the right pH in order to develop healthy plants.

Q:We have three dogwood trees in front of our house that appear to be slowly dying. Some limbs on the trees have completely lost their leaves, and other limbs have only a few leaves still on the branches. The trunk and limbs of one of the trees has a growth that looks like lichen or moss growing on it. I don't see any insects, but I've read that there is a beetle infesting trees in Virginia but I thought that only pine trees were affected. Do you have any idea what's happening to these dogwoods?

Answer: There is a borer that attacks dogwood Dogwood borers typically infest trees that have been weakened by something else. Check the base of the tree and see if the bark is broken or damaged. Mower and string trimmer damage often open up small wounds that allow the borer attack. Also, tall grass around the base of the dogwood provides a place for the adult of the borer to hide and lay eggs on the trunk.

If you don't see any damage on the lower trunk, you might want to have a certified arborist look at the trees for you. Without seeing the trees I can't make a guess as to whether they will survive or not. But an examination by an arborist should get to the root of the problem.

Richard Nunnally is a freelance writer and host of WCVE's monthly gardening show, "Virginia Home Grown." He can be contacted at .