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Improve your Garden's Soil

"Applied correctly, a soil amendment conserves moisture, improves infiltration of rain or irrigation water, and 'unlocks' existing nutrients in the soil." In using this method the nutrients in your soil are more readily absorbed and run-off is reduced.

A "soil amendment" is any addition to the soil that improves its chemical or physical condition. Amendments include changing pH and nutrient levels as well as amendments to improve soil qualities.

Optimum plant growth occurs when the soils pH is correct. Lime and sulfur are commonly used to balance pH, dolomitic limestone adds magnesium and calcium to increase pH (more alkaline), and elemental sulfur acidifies soil. How much should you add? That depends on the soils current pH and the desired pH. This is one good reason to have your garden soil checked periodically. (For more information about having your soil tested check out this Virginia Cooperative Extension web site:

Wood ash raises soil pH but must be applied twice as much as limestone to get the same effect and the pH must be checked yearly. Spread it in a thin layer on top of the soil then incorporate it. "Never use coal ashes or large amounts of wood ash (no more than 20 pounds per 1000 square feet), as toxicity problems may occur."

To improve soil nutrient levels, such as potassium, add greensand or granite meal. Finely ground granite rock, (granite meal) releases its potassium slowly. Greensand is relatively low in potassium and is readily dissolved. Other natural nutrient amendments for garden use include leather meal, cottonseed meal, kelp meal, and worm castings. (There are wide arrays of synthetic fertilizers as well.)

Improving soil quality typically requires a serious, long-term program of regularly adding cover crops, manures, compost, and other organic matter that can raise soil structure and nutrient level. (Sometimes to the point that the use of synthetic fertilizers is no longer needed.)

Animal manures are common garden soil amendments; however, fresh poultry, rabbit, sheep, and horse manures are "quite high" in nitrogen and thus more likely to burn plants. As such, they are best applied in the fall.

Compost is one way in which to get around tying up nitrogen during the decomposition process. Composts, usually made by gardeners from plant wastes, can result in valuable nutrient and humus (dark, fluffy product resembling soil) sources for any garden.

"Remember, your soil is alive and constantly changing. By keeping it fertile and rich, many gardening problems may be diminished. Soil is the base for plant growth, and much attention should be paid to getting and keeping it in the best condition."

Provided to you by the Virginia Department of Conservation & Recreation.