Soil test, compost are the key to fertilizing the vegetable garden | House & garden

F • How do I know how much to fertilize my vegetable garden without harming my plants or the environment?

Getting a soil test by your local county office is the best way to determine if your soil needs fertilizer.

Nutrients are important for plant growth, but adding in large amounts can be harmful to the environment and more likely to harm than help your plants. Many soils that have not been intensively cultivated in the past are rich in nutrients. If you do a soil test every three to five years, you can determine if your soil is depleted of certain nutrients.

The # 1 nutrient that most plants consume on a regular basis is nitrogen. How much nitrogen your soil needs depends on the specific crop you are growing and the amount of organic matter in your soil. The math can be tricky, but with the information from your soil test and a fertilizer calculator like this one, it can get easier:

In addition, adding compost regularly is the best way to build up your soil’s organic matter, and it’s one of the best slow release organic fertilizers available. As the organic matter breaks down, it slowly releases nitrogen and other nutrients that feed your vegetables during the season. For more information on fertilizing vegetables, see the University of Nebraska-Lincoln online publication:

Write to the Missouri Botanical Garden’s Center for Home Gardening at or the Horticulture Answer Service, 4344 Shaw Blvd., St. Louis, MO 63110.

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