DATE: Sunday, May 25, 1997                  TAG: 9705240055

SECTION: HOME                    PAGE: G3   EDITION: FINAL 

SOURCE: BY ROBERT STIFFLER, GARDENING COLUMNIST 

                                            LENGTH:  108 lines

BERMS MAY SOLVE DRAINAGE PROBLEMS

I bought a new house in the Great Bridge area of Chesapeake last summer and installed a sprinkler system with a well. We enclosed the back yard with a 6-foot wood fence and last October took the big plunge and sodded the yard. When I got my permit to install the fence, I was required to plant three understory trees and 18 shrubs. My plans to do this have run afoul.

The soil in this area is what they call ``blue clay.'' It is so poor that a dog wouldn't even ``visit'' it. In an effort to give the trees and shrubs a decent growing medium, I rented a small excavator and dug out three areas in a semicircle, along the fence, 9 feet wide and 3 to 4 feet deep. I filled these with topsoil and then planted three beautiful crape myrtles and ringed them with azaleas. Water is collecting and holding in these beds. I dug a hole in one of them and it was like a stew pot, just a foot below the surface. I'm sure that if left alone, root rot will take place.

To improve drainage, I spread about 400 pounds of gypsum before sodding and put some in the bottom of the beds, but that doesn't seem to help. Even the yard holds water for days. I imagine the yard will improve as grass roots go deeper, but I need help with the beds. I thought about having the guy who dug my well come back and drill a hole in each bed through the clay, which was about 18 feet down. Any ideas?

Scott Jones, Chesapeake

It appears you may have done just the opposite of what will work to solve your problem. The holes you dug and filled with good soil act as a reservoir or sponge. They accept and hold the water, complicating your problem. Virginia Tech specialist Bonnie Appleton says perhaps your only solution is to build berms. They are small mounds of soil, used to camouflage ugly areas. They can be built in any size and shape you want. They should be 12 to 18 inches high but can be as high and large as you want. Then the roots of your plants will have proper drainage and not rot.

You mentioned drilling through the clay. This sometimes works, by making a dry well, which is a large hole filled with small rocks. You drill your hole through the clay under the dry well, so water drains away. To help your situation, you'd probably need to regrade your property so everything drains toward the dry well. And you might need more than one. Building berms and replanting your plants is probably the best long-term solution, although costly and time-consuming.

A third possibility would be to install those perforated black tube-like drainage pipes throughout your yard, under the topsoil. You'd then drain them to some low spot on your property. Any of the methods suggested is going to take considerable time, patience and money.

In a column last fall, you had a reader question about a vine growing in Edenton, N.C. The plant is Smilax smallii, commonly called Jackson vine or Bamboo vine. It is very attractive and a lot of people train it on a wire above the front door, where it forms an arch. This evergreen vine is mostly thornless, unlike the noxious Smilax species in our gardens. It's available from Woodlanders, the mail-order supplier in Aiken, S.C.

Another reader asked about one in a pair of azaleas that wasn't growing well. One cause not mentioned might be that the unhealthy plant was planted too deeply. I've dug many an azalea to discover it was too deeply planted. Often these plants continue to live but don't grow or bloom.

Brian O'Neil, Virginia Beach

Brian O'Neil is owner of Southern Meadows Landscapes in Virginia Beach and a knowledgeable plant person. He can be reached at 479-4765.

Smithfield Gardens tries to stock Smilax smallii, but it is often difficult to find.

You have had several articles on aggressive bamboo. I am a retired Army officer and have been growing bamboo for years. I have been stationed in the Philippines, Japan and Hawaii and have seen bamboo growing wild in all those countries. I've also seen the problem your readers write about. I currently have bamboo growing in my yard with no problems.

There is a solution. Use the KISS principle - Keep It Simple Stupid. First, I went to the hardware store and bought black plastic rain catchers that you use under gutters. They are 2 feet by 3 feet by 6 inches deep. Then I drilled eight to 10 one-inch holes in the bottom of them and covered the holes with black plastic WeedBlock. I filled the container with Pro Mix and planted the bamboo. I have several containers in the back yard and have no problems with bamboo spreading.

John S. Fraser, Virginia Beach

If this works for one, it should work for others. If you can control bamboo, you've solved a major problem for many homeowners.

In late fall last year, you wrote about birds not being attracted to your rose hips or crab apple fruits and asked what readers had observed. I have shrub roses that have large hips. In the fall, they swell to the size of large cherry tomatoes. Cardinals love them. They have been on my roses all through the fall, and I counted eight cardinals on one bush.

I also have dwarf crab apples that have white flowers in spring and pea-size fruits in fall. For the last three years, the same mockingbird has guarded and gorged on this fruit. The cardinals sneak in and grab a fruit when they can.

My yard is full of birds year around. I am delighted to see you recommend organic solutions more often. I became organic 10 years ago and my yard, flowers and vegetables are very healthy without the use of fertilizer or pesticides.

Doris D. Mow, Chesapeake

Thanks for an interesting letter. We have shrub roses near a feeder the cardinals like, so next year I'll leave on the rose hips and see if the cardinals will eat them.

I have a problem with azaleas. They look like they have coal dust all over them.

R.T. Baldwin, Virginia Beach

Virginia Beach extension agent Randy Jackson says it's most likely sooty mold. Azaleas usually do not have such a problem, but if they're under a pine tree, the pine tree probably has aphids, and their excretions can result in sooty mold. The solution is to spray the tree with malathion or Orthene. If that doesn't stop the problem, it could be caused by scale. For that problem, you spray with horticultural oil before hot weather. MEMO: No gardening questions will be taken over the phone. Write to

Robert Stiffler, The Virginian-Pilot, 150 W. Brambleton Ave., Norfolk,

Va. 23510. Answers will be published on a space-available basis. For an

earlier reply, send a self-addressed, stamped envelope.

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