Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SUNDAY, April 8, 1990 TAG: 9004090429
SECTION: HOMES PAGE: D-1 EDITION: METRO
SOURCE: JOHN ARBOGAST
DATELINE: LENGTH: Long
Mowing seems to be the most time-consuming lawn job at this season. The hours that it requires may cause some simply to get the job done with the least amount of work. However, the importance of doing it correctly is critical, since this affects the health and vigor of the turf the rest of the year.
Turf grass should be mowed often enough so that no more than one-third of the blade height is removed at one time. Removing more reduces or even stops root growth, so says research done at the U.S. Department of Agriculture several years ago. For turf to survive hot, dry summer periods a deep root system is required.
If the one-third rule is followed, there should be a small amount of grass clippings, which should be left on the grass surface in order to return nutrients to the soil. Larger amounts of clippings are unsightly, of course, and may cause smothering or heat injury to the turf. These should be raked. Grass clippings do not contribute to thatch.
Start the year off by unpluging the sparkplug and setting the lawn mower at the proper cutting height. Recommended heights in inches for the types of grass grown in the Roanoke area are: cool-season grasses (most lawns here) such as Kentucky bluegrasses _ 2 to 2 1/2; tall fescues _ 2 1/2 to 3 inches; and warm season or southern grasses _ bermuda and zoysia _ 3/4 to 1 inch.
Since with many new mowers it is difficult to set the mower on a hard surface and get a measurement of the cutting height, use the height adjustment levers by the wheels, which may have variations of low, medium, or high settings and observe the cutting effect. The bottom setting on these may be for very short cutting of 1/2- to 3/4-inch heights, while the upper settings may be for 3 inches and taller. Turf grass mowed short, especially bluegrasses, is more likely to have weed problems.
Since we want to encourage healthy turf without the need for fungicides, it is important that the lawnmower blade be sharp. A dull blade actually injures the grass plants as it tears the tops off. This weakens the turf plants and may allow disease organisms to enter.
The application of readily available nitrogen fertilizer to bluegrass or fescue lawns at this time is not recommended due to the negative effect that top growth stimulation now can have on the roots. Cool-season grasses that are very lush in the spring stand a greater chance of suffering from summer stress problems and becoming susceptible to turf disease. Warm-season turf, on the other hand, may benefit from nitrogen applied in the spring.
Broadleaf weed control also is a concern for some at this time. For cool-season turf, "weed and feeds" are out of the question at this time. An application of an appropriate weed killer by itself to contact weeds in selected areas might be effective, although many spring weeds, such as dandelions, chickweed and white clover, are better controlled in the fall and may be too tough now. Common leafy weed killer chemicals for the lawn available to homeowners are 2,4-D, dicamba, mecoprop and combinations of those. Follow the label directions for amount to use and precautions such as avoidance of use in hot weather.
Q: I have a problem with my violets. I have nine that are in the shape as this sample I am sending you. I don't think I water them too often. I have repotted some of them, and they get in this shape after I pot them. It seems that the section in the heart of them stops growing. Please tell me what is the trouble. I use violet potting soil and that still doesn't stop this trouble. M.B.C., Salem
A: Plant samples sent through the mail often arrive in poor condition, especially if they have to sit for awhile in a mailbox. Thus, the violet parts you mailed were decayed and growing mold when I got them. Since you said that the problem occurs after you repot your violets, the cause may be that the soil is staying too wet in the larger pots causing a similar result as overwatering.
Maybe that's why the sample decayed so fast after you mailed it. It might be that the roots are injured in repotting or that you're burying the roots when you repot.
The best suggestion is to call the Extension office that serves your area and let them ask you questions that may lead to a diagnosis or give you instructions on bringing them a fresh sample. You are served by the Roanoke County Extension Office, located near the Salem Civic Center, 962 Kime Lane, Salem, telephone 387-6113.
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.
GARDENER'S CHECKLIST
Bulbs: Don't be in a hurry to remove the foliage of spring flowering bulbs. The leaves manufacture the food for the bulbs, which is stored down in the bulb for next year's bloom. If the foliage is removed prematurely, the bulb may not flower next spring.
Pyracantha: For more compact pyracantha bushes, pinch back the new growth now. This will avoid the risk of losing the crop of berries by pruning after flowering.
Forsythia: When pruning forsythia, do not shear as you would a hedge. Thin out the oldest branches as close to the ground as possible. Then, reduce the size of the excessively long branches using hand pruners. This should be done immediately after blooming.
by CNB