List of Fertilizers

There are two types of fertilizers: chemical and organic. Chemical fertilizers should be applied in the spring, prior to planting. This type of fertilizer doesn't need to be worked into the soil very deeply; about three to five inches will suffice. Organic fertilizer can be applied in the fall or spring. It can be plowed into the soil five inches or so, or can even be placed right on top of the soil.

Compost

The least expensive and most ecologically friendly fertilizer is compost. If you start your own compost pile, the material is free. You just compost your vegetable scraps and other organic material until it begins to break down. If you place the compost matter into a bin that reaches 140 degrees, your compost will be ready to use in as little as two weeks. You can till compost into the soil or spread it over the top.

Manure

This organic fertilizer should be applied in the fall and only after it's well rotted. New manure can burn plants. Because of possible E. coli or salmonella presence, manure should only be applied at least 120 days before planting, and never used as a side dressing.

Cover Crops

Cover crops are small, green plants or legumes that are grown for the sole purpose of acting as fertilizer for the soil. While they are still green. they are plowed under in order to decompose and add nutrients to the soil.

Chemical Fertilizers

Chemical fertilizers come in two varieties: liquid and dry powder. Liquid fertilizer is fast-acting but must be re-applied every two to three weeks. It comes concentrated and is added with water and applied with a sprayer or watering can. Dry powder fertilizer must be watered after application. It comes in two varieties: quick or slow release. The quick release fertilizers are water-soluble and last up to four weeks; the slow release are water-insoluble and last eight to 12 weeks. Chemical fertilizers contain three main ingredients: nitrogen, potassium and potash. The percentages of each ingredient are marked on the bag. For instance, 10-10-10 fertilizer contains 10 percent of each of the three ingredients. The remaining 70 percent is inert material such as limestone or clay. The inert ingredients help distribute the nutrients evenly and also prevent them from burning the plants. Nitrogen is used to promote leaf growth and helps the plant develop a dark green color. On the bag of fertilizer, nitrogen is marked as N. Phosphorus promotes strong root growth. It is marked as P. Potash, or potassium, is marked as K on the bag. It helps root development and also helps the plant resist disease.