Allen Wilson


Question: My friend suggested I add some bark dust to my vegetable garden before planting. Will that improve my garden?

Answer: Incorporating organic material into your vegetable garden and annual flower beds will improve growth and yield. I like to add 2 or 3 inches of grass clippings, leaves, compost, bark dust, peat moss or other available materials and spade or till them in a month or more before planting. Organic matter will also improve the growth of trees and shrubs.

Instead of disposing of accumulated leaves and leftover plants, spread them over beds and incorporate most of them. All but the coarsest materials can be spaded or tilled under, even without composting. Coarse materials like corn stalks and broccoli plants can be composted in an out-of-the-way spot for use next year. They will deteriorate faster if chopped into smaller pieces, and finer materials, such as grass clippings and leaves, can be added during the summer and fall. Aspen leaves should not be composted or tilled into the soil. The black spots on aspen leaves will re-infect new growth and make the problem worse.

Before tilling, add a light application of ammonium sulfate, lawn fertilizer or Natural Guard soil activator to speed up the breakdown. You will be surprised by what the earthworms and microorganisms will do in a month.

After incorporating organic matter, raise and shape flower beds for maximum beauty. Side beds should be shaped so that they are higher in the back than the front. This will tilt beds so that the maximum color is exposed to the eye. Make a sharp edge along the lawn and lower the soil next to the grass a couple of inches. Rake this soil toward the back of the bed. Island beds can be shaped highest in the center. Now is a good time to add wood, metal or plastic edging to keep grass from growing into beds.

Now is also a good time to remove grass or weeds around shrubs, raspberries, roses and trees. Make sure you dig deep enough to remove the roots of grass and perennial weeds. Casoron granules can be applied to kill existing grass and prevent weed growth all summer. Do not use Casoron where you intend to plant flowers or any other shallow-rooted plants. Mulching shrubs, berries and trees with bark dust will also greatly reduce weed growth. Weed barrier fabric can be placed under trees and shrubs to completely shade out weeds before covering with bark dust.

If you will be planting new shrubs and trees this spring, incorporate organic matter into the soil at least three times the diameter of the root balls. When planting several shrubs, add organic matter to the area between shrubs, not just in the planting holes. Roots will soon grow into these adjoining areas. Young trees will grow about twice as fast if at least a 3-foot circle is maintained free of weeds and grass with mulch on top. This also prevents damage to tree bark from mowers and trimmers.

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