Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SUNDAY, May 2, 1993 TAG: 9305030312
SECTION: HOMES PAGE: E-1 EDITION: METRO
SOURCE: John Arbogast
DATELINE: LENGTH: Medium
A: Bark completely coming off a limb of any plant indicates that the limb has died.
It would be hard for me to say whether your azalea's leaves turned brown first as an early symptom of trouble or that the plant began dying from some unknown cause that caused both the loosening of the bark and the discoloration of those leaves at about the same time. Anyway, it is likely too late for your azalea now to be treated for any hope of recovery.
Partial browning of leaves of an azalea usually indicates that the plant is under some kind of external stress, such as drought injury, high winds, heat or possibly a soil problem. Major browning of azalea foliage often indicates that the roots are rotting, either from a disease such as phytophthora root rot or from too much moisture in the soil.
Q: My smoke tree was heavily damaged by the blizzard. How drastically can this be cut back and when is the best time to do it? Will cutting back hinder flowering of it in the future? G.J.N., Salem
A: The common smoke tree or smoke bush can be cut back by as much as half or even more if the work is done in the late winter or very early spring prior to the growth's coming out.
Michael Dirr, author of "Manual of Woody Landscape Plants," has remarked that often the purple-leaf types are cut to the ground in late winter to force vigorous shoot growth that is more colorful than the normal shoot extensions. So, cutting back at the proper time should not hinder its flowering in the future.
Readers should note that storm damage to any plant should be corrected just as soon as weather permits. Then, additional pruning or shaping can be done at the appropriate time for a specific plant.
Q: My lilacs have a problem. Every spring shortly after they bloom and get new leaves, the leaves turn dark and fall off. In September, new leaves and blooms appear and the leaves again turn dark and fall off. Can you help me? Mrs. K.Y., Daleville
A: Because regrowth of your lilacs goes through the same symptoms late in the season as the plants experience in the spring, the problem must be from some adverse condition on the plants' site. I have no idea what that adverse condition is.
Are the new leaves and blooms that appear on the old shoots that were affected in the spring, or is that new growth coming out below those parts injured in the spring? This kind of fact, as well as other descriptive details, should be known in order for a diagnosis of the problem to be made by a plant clinic.
The only disease that I am aware of that lilacs sometimes get in the spring - with symptoms somewhat similar to the first phase of yours - is called bacterial blight, so-named because it is caused by a bacterium. This disease can seriously damage lilacs during cool, wet weather, but I have not heard of it occurring in the late summer or fall when our weather usually is drier.
If your lilacs produce those symptoms again this year, take a fresh sample to the Botetourt County Extension Office and ask that the sample be sent to the Plant Clinic at Virginia Tech. That Extension Office is in the Historical Building just west of the courthouse in Fincastle; telephone 473-8260.
Got a question about your garden, lawn, plants, or insects? Write to Dear John, c/o the Roanoke Times & World-News, P.O. Box 2491, Roanoke, Va. 24010-2491. Gardener's checklist
Jobs for early May:
Prune winter-killed wood on trees and shrubs by cutting back to green wood after new growth begins.
If your lawn is bluegrass/fescue, resist the urge to fertilize now. Fall is the time for fertilizing these grasses. Fertilizing now will keep you behind the lawn mower all spring and increase chance of injury to your lawn from summer disease and drought.
Newly transplanted flower and vegetable plants would be protected from cutworms with collars. Cut strips of cardboard 2 inches wide by 8 inches long and staple them into a band to be placed around the plants. Press the collar about 1 inch into the soil.
by CNB