Originally created 02/15/02

Tips offered for organic growing



Increasingly, gardeners are wanting to grow plants in the most natural way possible - without the use of chemicals, inorganic fertilizers, artificial pesticides and growth regulators.

These organic gardeners compost organic matter, use mulches and recycle organic wastes to keep their soil fertile.

The theory behind their method is valid, although following their recommendations too closely can be impractical or oppose sound scientific principles.

Successful organic gardening begins with knowing established gardening practices based on horticultural principles.

All vegetable gardeners, organic and inorganic, should:

  • Choose a good location in full sunlight. You need a minimum of six to eight hours for most plants to do well.
  • Plan the garden layout on paper so the crops have enough room and don't shade each other.
  • Grow varieties adapted to our area.
  • Use good seed, plants and supplies.
  • Plant seeds and transplants properly.
  • Use mulches whenever possible.
  • Water properly.
  • Harvest crops at the proper time.
  • Control weeds, insects and diseases.
  • Certain additional practices need to be stressed when you try to grow vegetables organically:

  • Use disease-resistant varieties. One good way to get superior plants with desirable characteristics is to grow hybrids. Hybrid plants are uniform and usually stronger, healthier and more productive than open-pollinated varieties.
  • Build a healthy soil. The success of a garden depends largely on the fertility and structure of the soil. A loose, well-drained and well-aerated soil enables roots to grow well and lessens the occurrence of seedling blight and root-rot disease.
  • Clay or poorly drained soils can be improved by planting green manure crops or by adding compost, peat moss, straw, hay, leaves, grass clippings or other organic soil conditioners. Adding organic matter to almost any soil each year is a good idea and necessary for good structure.

    Vegetables prefer fertile, well-drained soil with a pH of 6.0 to 6.5.

    Gardeners commonly add lime to their soils every year, but unneeded lime can create problems that aren't easy to correct. A simple soil test can tell you how much lime and other elements your soil needs. Take a mixture of samples, taken randomly 6 inches deep throughout the garden, to your county extension service office.

  • Maintain a fertile soil. Plants need 16 elements to grow. Of these, nitrogen (N), phosphorus (P) and potassium (K) are the most important. Carbon, hydrogen and oxygen are provided by air and water and seldom limit growth. Calcium and magnesium are supplied by liming. Plants get sulfur from decomposing organic matter and rainwater.
  • The remaining elements, referred to as micro-nutrients or trace elements because they are required in such small amounts, include iron, copper, boron, chlorine, manganese, molybdenum and zinc. These elements rarely need to be added when large amounts of compost are used. The sandy soil of some parts of Richmond County and areas to the south may be lacking in trace minerals.

    Natural sources of nutrients are meal, greensand, dried blood, fish meal, cottonseed meal, rock phosphate, muriate of potash and wood ashes.

  • Use soil-building materials. Although the amount of nitrogen in manure varies according to its source, most fresh manure from cattle or horses contains only about 0.5 percent nitrogen. This is about 1/20th of the nitrogen found in an equal amount of 10-10-10 fertilizer. So about 20 times more manure would be needed to supply about the same amount of nitrogen found in 10-10-10 fertilizer.
  • Cricket manure is actually a better source of nitrogen (4 percent nitrogen), so it goes much further than animal manure. Animal manure is much harder to come by in urban/suburban areas, so cricket manure makes even more sense to use. If no manure is used, compost is a good substitute.

    A compost pile consists of layers of plant matter that have been mounded and allowed to decompose until dark in color and readily broken up. The final product can be mixed into the soil to improve structure and fertility.

    Sid Mullis is director of the University of Georgia Extension Service office for Richmond County. Call him at 821-2349, or send e-mail to smullis@uga.edu. The offices that serve Richmond and Columbia counties have a Web page at www.griffin.peachnet.edu/ga/columbia.