ROANOKE TIMES
Copyright (c) 1996, Roanoke Times
DATE: Sunday, December 15, 1996 TAG: 9612170093
SECTION: HOMES PAGE: D-2 EDITION: METRO
COLUMN: Dear John
SOURCE: JOHN ARBOGAST
The Roanoke Extension Office will present a six-part Integrated Pest Management school open to the public this winter to help consumers, garden center workers and grounds maintenance workers.
Classes in this series will be held on each Thursday from Jan. 30 to March 6 from 1 p.m. until 4 p.m. in the large meeting room in the Roanoke County Brambleton Center, 3738 Brambleton Avenue S.W., Roanoke.
Since the class topics build in sequence, participants should plan on attending all six Thursdays. Preregistration and payment of the $5 fee for the entire series is required before classes start. Contact the Roanoke City Extension Office, 541 Luck Avenue S.W., Suite 317, Roanoke, (540) 857-7915.
The first class on Jan. 30 will give an introduction to IPM. Subsequent classes will be on "Basic Botany," "Lawn Establishment and Lawn Maintenance," "Landscaping to Reduce Problems and Selection, Use and Care of Woody Ornamental Plants," "Ornamental Plant Diseases and Diseases In-home food Production" and "Basic Insect Identification and Household Insects."
If you are a person with a disability and need any assistive devices, services or other accommodations to participate in the classes, please contact the Roanoke City Extension Office (857- 7915) between 8:30 a.m. and 5 p.m.
Q: I would like to know how to winterize rhubarb in the fall. Also, how do I break the roots apart to divide rhubarb in the spring? What kind of fertilizer should I use on rhubarb? H.S., Wytheville
A: The main late-fall practice that will winterize rhubarb is cutting and removing all leaves with stalks and seedheads. Do not be tempted to eat rhubarb leaf stalks, even if they look OK. Once hit by frost the oxalic acid, which is the poison in the leaves during the growing season, can move from the leaf blades to the stalks.
Mulch over well-established plants is usually not advised because it might hold moisture around the roots and create conditions for root rot.
Also, rhubarb needs frozen soil to properly make it through the winter, which is why we don't see rhubarb grown in most parts of the deep South.
In early spring, just as soon as you know where to dig, remove root clumps of plants that have been in the same spot five or more years and divide. When dividing, use a sharp cutting tool and be sure to include as much root as possible and at least two strong buds on each division. Don't allow the divisions to dry out before replanting.
The best fertilizer for rhubarb, as well as any other vegetable or the whole garden, should be selected based on a soil test done at least once every three years. Rhubarb is considered a heavy feeder and might do well if one-half cup of 10-10-10 is scratched into the soil around each established rhubarb hill in the spring.
However, if phosphorus and/or potassium levels are already high in your soil, a nitrogen-only fertilizer would be a better choice.
Q: The highway department has planted crown vetch on embankments along roads near my property. It has gotten into my landscape ground cover, particularly the periwinkle. How can I get it out without also destroying my ground cover? The areas are quite large, so digging the crown vetch out by hand would be impractical. G.D., Blacksburg
A: Virginia Tech's Pest Management Guide for the Home Grounds does not have a recommendation for your problem. Your choices are: do nothing - just live with the situation; or apply Roundup or Kleenup as spot treatments only to the visible, actively growing crown vetch plants in late spring. Take care not to get any chemical on the periwinkle. Selectively kill the crown vetch plants (tedious and maybe out of the question if the periwinkle bed is more than 4 feet across or steep). You might dig out the crown vetch plants next spring before they bloom (also tedious and, as you wrote, impossible). Another possibility is to check with knowledgeable garden-center or nursery staff in the spring to see if any new products are available in 1997 for noncertified applicators to purchase and use to remove the crown vetch.
Send short questions about your lawn, garden, plants or insects to Dear John, c/o The Roanoke Times, P.O. Box 2491, Roanoke, Va. 24010-2491.
Gardener's checklist
Jobs for mid to late December:
Minimize foot and vehicle traffic on the winter lawn if at all possible.
Use a soft, damp cloth to remove the winter dust accumulation from indoor plant leaves.
Look at your landscape now in the winter to see if you have plants costing you energy dollars, such as tall evergreens blocking the sun s warmth from certain windows.
John Arbogast is the agricultural and natural resources extension agent for Roanoke.
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