Using Organic Fertilizer - Animal Manure, Seed Meals and Lime

Healthy plants that produce a wealth of healthy food can get a well needed boost from some type of fertilizer. Composting can provide this, but there are other ways to fertilize.

One of the best sources of organic fertilizer is animal manure. Cow, chicken, rabbit, horse and mink are among the most readily available in many parts of the world. It is best to use them after they have had a chance to rot for a few years. They provide some plant nutrients, favorable bacteria, humus, better aeration and they help retain more moisture when they are mixed with your garden soil.

Manures are available from dairy farms, riding stables, and poultry farms. Usually you will have to pick them up from these sources, using your own truck. Sometimes firms that deliver soils or mulches will also stock and deliver one or two types of fresh or well-rotted animal manures. A check of the want-ad section of the newspaper will often reveal additional sources of supply.

If you use fresh manures, they are best applied in the fall, as they are apt to burn or retard plants if they are applied during the spring, growing season. Well-rotted manures can be used in the spring. You should apply the fertilizer around the base of the plant.

You can use either fresh or rotted manure to make a liquid-tea to feed plants. The tea is usually made of one part of manure and ten parts of water. Let it set for several days before you use it then spray directly on the plant.

The process-dried manures are often available at garden shops and can be used for top-dressing or they may be mixed into the planting soil. Fish meal, blood meal, bone meal, animal manures, cottonseed meal and processed sewage sludge are organic sources for nitrogen fertilizer. Phosphate rock and bone meal are the two organic fertilizers used to supply phosphorus. Wood ashes and rock potash are the two main sources of organic potassium.

Your local garden department will generally stock any of the above organic fertilizers. You can also make your own fertilizer. Look in our recipe section!

When it comes to fertilizers, Seed meals and various kinds of lime are the most important ingredients. These alone will grow a great garden. Seed meals are byproducts of making vegetable oil. They are made from soybeans, flaxseed, sunflowers, cotton seeds, canola and other plants. Different regions of the country have different kinds more readily available. Seed meals are stable and will store for years if kept dry and protected from pests in a metal container with a tight lid.

Lime is ground, natural rock containing large amounts of calcium, and there are three types. Agricultural lime is relatively pure calcium carbonate. Gypsum is calcium sulfate and is included because sulfur is a vital plant nutrient. Dolomite, or dolomitic lime, contains both calcium and magnesium carbonates, usually in more or less equal amounts. If you have to choose one kind, it probably should be dolomite, but you'll get a better result using all three types. These substances are not expensive if bought in large sacks from agricultural suppliers.

Organic fertilizers are much more conducive to the environment and the health value of our foods than the traditional chemical fertilizers. Why?

Organic fertilizers, manures and composts release their nutrient content only as they decompose -- as they are slowly broken down by the complex ecology of living creatures in the soil. Complete decomposition of most organic fertilizers takes around two months in warm soil. During that time, they steadily release nutrients.

With non-organic fertilizers, overdosing can be a real problem. They are so strong that it's easy for inexperienced gardeners to cross the line between just enough and too much.

Yet, despite their strength, inexpensive blends are incomplete. They supply only nitrogen, phosphorus and potassium. Unless the manufacturer intentionally adds other essential minerals, the chemical mix won't supply them. Chemical fertilizers rarely contain calcium or magnesium, which plants need in large amounts along with tiny traces of several other minerals.

Inexpensive chemical fertilizers dissolve quickly in soil. This usually results in a rapid burst of plant growth, followed five or six weeks later by a big sag requiring yet another application. Should it rain hard, the chemicals dissolved in the soil water will be transported as deeply into the earth as the water penetrates (this is called "leaching"), so deep that the plant's roots can't reach them. With one heavy rain or one too-heavy watering, your fertile topsoil becomes infertile. The chemicals also can pollute groundwater. The risk of leaching is especially great in soils that contain little or no clay.

Chemical fertilizers can be made to be "slow-release," but these sorts cost several times as much as those that dissolve rapidly in water. The seed meals in an organic fertilizer mix are natural slow-release fertilizers, and they usually are less expensive than slow-release chemical products.

You should fertilize your plants once every three to four weeks. You will want to pay attention to how your plants are doing and fertilize accordingly. Some plants need more fertilization attention than others.

Beans, peas, and carrots are among the low demand vegetables for fertilizing. They need fewer requirements for additional nutrients than the medium demand plants.

Most garden plants are medium demand plants. These would include tomatoes, corn, squash, zucchini, cabbage and peppers. Be careful not to over-fertilize these plants. A good rule of thumb is 4-6 quarts of fertilizer per 100 square feet with a ¼ inch layer of compost.

Some high demand vegetables are artichokes, cauliflower, turnips, and spinach. These will require the same 4-6 quarts of fertilizer per 100 square feet, but you need to increase the compost layer to ½”.

High-demand vegetables are sensitive, delicate species and usually will not thrive unless grown in light, loose and always-moist soil that provides the highest level of nutrition.

Of course, you need to stay on top of the weeding to insure your plants have enough room to grow and that those weeds don’t steal away their food!

We suggest tending the garden at the same time every day. Morning would be best since it is cooler during the summer and you won’t have to bear the oppressive heat. Don’t let the weeds take control. This is why we recommend doing so every day so that you won’t have a huge job if you neglect it for a week or so.

Taking care of a garden might require you to get on your hands and knees to pull weeds from the middle of your bean plants or cabbage rows, so do this. It’ll save stress on your back and, of course, bring you closer to the natural environment that is your organic garden!

Then just sit back and wait for the benefits of your garden – fresh produce! Of course, the successful gardener knows that once cold weather arrives, their job isn’t quite done.

Next article: Wintering Your Organic Garden

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