As more and more gardeners are practicing organic gardening, adding compost is one of the most popular methods. But why is compost so beneficial?

Many gardeners add compost to the landscape or vegetable beds as a fertilizer. Compost contains the macro nutrients needed by the plant. There are nutrients that inorganic fertilizers provide, such as nitrogen, phosphate and potash. But compost contains these nutrients in much lower quantities. A typical nutrient analysis on a bag of manures is 1 percent nitrogren, 0.5 percent phosphat and 1 percent potash. Gardeners may need to use eight to 10 times the amount of compost to yield the same results that a 10-10-10 inorganic fertilizer would provide.

These three macronutrients are not everything a plant needs. Plants also need secondary nutrients, such as sulfur, calcium and magnesium. Though these nutrients are needed in lower amounts than the macronutrients, a substantial amount is still needed for the plant to thrive and is provided by the added compost.

Compost also is an excellent source of micronutrients including zinc, boron, iron and copper.

Compost also can help improve soil conditions. Particles of humus derived from compost have a negative charge while most of the nutrients plants need carry a positive charge. Incorporating compost into a native soil helps retain the naturally provided nutrients plants need in the soil by preventing them from leaching or running off.

Incorporating compost into the garden also helps with water retention. The organic material acts like thousands of tiny little sponges, absorbing water, then slowly releasing it to the plants at a later time.

Compost can be added to the gardening area at a rate of 450 pounds per 1,000 square feet. If your gardening area is not this big or you don't have the means to weigh the compost, a great rule of thumb is to add 1 to 2 inches of compost. Use a tiller to mix it into the soil where there are not established plants. In areas where plants are present, use a hand-held cultivator to work compost into the soil.

Adding compost to the garden can prove to be very beneficial, but is not a silver bullet. Be sure to continue to take a soil sample every two years to ensure that the nutrients being provided are what are needed for your garden to thrive.

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