ROANOKE TIMES

                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: SUNDAY, May 13, 1990                   TAG: 9005140356
SECTION: HOMES                    PAGE: D-1   EDITION: METRO  
SOURCE: 
DATELINE:                                 LENGTH: Long


MAINTENANCE HELPS ENSURE ROSES' BEAUTY

Rose growers living in Roanoke (including this Extension agent) have found that the winter damage to bush roses was severe to certain roses, and replacing rose plants next spring may be required after we find that the growth that was left is suckers that follow the death of the grafted parts.

Assuming that rose gardeners have already done the recommended early spring pruning on bush roses to remove excess growth, winter-killed parts, and diseased areas, you can enhance the beauty of their plants at this time of the season through five maintenance chores. These chores are periodic fertilizing, mulching, weed control, disease and pest control and watering if needed.

Periodic fertilizing every four to six weeks is suggested from March through July since most of our bush type roses are ever-bloomers, meaning that a continuous supply of a moderate amount of nutrients will promote constant new growth and thus more and more blooms. Packaged rose foods can be used according to the package directions or 5-10-5 or 5-10-10 can be scattered at the rate of four tablespoons per plant.

Many kinds of organic mulch can be used in a 2- to 3-inch layer in the rose bed. However, it is important not to pile mulch over the graft union.

Most weed control around roses involves hand work. It is just too risky and thus not recommended to use herbicides after weeds have emerged around roses or other home ornamental plants. Maintaining mulch will reduce the potential for weed growth.

Many specialty products are available at various garden departments for rose disease and pest management. As always, users must follow label instructions if positive results are to be expected. An important factor for many of these products is the need for repetition as recommended. Also important is frequent observation of rose plants, so that problems can be detected and controlled early before things get out of hand.

Roses should be watered deeply once a week during dry spells so that nutrients will be utilized and growth will not be interupted. To help prevent diseases, water roses early in the day so that wet leaves will be quickly dried by the hot sun. Sunlight hitting the cool water droplets does not lead to scalding of plant parts, although water coming out of a hose that has been sitting in the sun will be very hot at first and could cause injury.

Although not in this mid-spring list of rose chores, most rose growers know that as soon as bush roses start flowering it is critical to prune out faded rose blooms as soon as they pass their prime in order to encourage more flower buds to form.

Q: Please tell me how to get grubs out of my lawn, the best time of year and what to use. R.D.R., Martinsville

A: The type of white grub that stays in the soil for all of the grub stage and feeds on the roots of turf can best be controlled when the grubs are young in middle to late summer. This is when grubs are found in damaging numbers. Be sure to roll back a square foot of turf from one of the browning areas at that time to check for the presence of grubs before treating. The loosened piece of sod can be replaced, stepped on and watered periodically after checking so that this test does not require tearing up the yard. If four or more grubs are found per square foot, treatment can be made with either diazinon, Oftanol, or the biological control called milky spore disease that is mainly effective against Japanese beetle grubs where insecticides are not used. Follow all label directions and be sure to water the treatment in to get the material under the soil surface where the grubs are.

Q: How often should fertilizer be put on the lawn? What type of fertilizer should be used? When should lime be put on the lawn and how often? C.B.C., Salem

A: Fertilizer should be applied to turf at the time of year that the roots will get the most benefit. For the so-called cool-season grasses, which include bluegrasses and fescues, this time is in the fall. For "warm season" grasses, which are the southern grasses bermudagrass and zoysiagrass, this is from mid-spring to midsummer. Complete fertilizers that have more nitrogen, which is the first number slot on the bag, than they do of the other major nutrients are considered "turf type" fertilizers. In some cases, soil tests from the grass may indicate a need for a fertilizer that contains nitrogen only rather than all three major nutrients or maybe a need for other specialty fertilizer.

If the fertilizer selected has most of the nitrogen listed on the label as quickly available, two or three moderate size applications can be made during that recommended time of year.

If the fertilizer you use has over 50 percent of the nitrogen in the slow release form, which will be listed as water insoluble nitrogen on the bag, make two applications during the suggested time. Lime can be applied to the turf any time of the year that the ground is not frozen, but ideally should be based on soil test results and recommendations, which will tell just how much and how often lime is needed to correct a low pH problem if indeed that problem exists.

Q: Please inspect these two shrubs. I am sending you a piece of each and would like your diagnosis and help. Mrs. A.C.O., Roanoke

A: You need to contact your local Extension office for help in diagnosing the problems and recommending an appropriate solution. Samples sent to me in the mail often arrive in poor condition, thus preventing diagnosis and description to other Dear John readers. Since your address is in Roanoke County, call 387-6113 for assistance. It is almost impossible to diagnose problems from small twigs with a few leaves, so anyone taking a sample to an Extension office or nursery must take a complete representative sample.

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.



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