Organic Fertilizer Facts

Overview

Organic produce is popular in the market but there are few standards to define what "organic" actually means. One of the components of produce is the nutrient mixture called fertilizer that is added to growing plants.

Fish provide many minerals to organic fertilizers

Identification

Organic fertilizer is a soil amendment made from animal or plant materials. Its primary function is to provide nitrogen to growing plants.

Bone meal added to fertilizer provides phosphate, calcium and magnesium

Benefits

Organic fertilizers' slow-release of nutrients, leads to more efficient use. Proper application can also lead to less fertilizer run-off into local waterways and point pollution of water tables.

Manure from farm animals, poultry--even bat "guano" is used as fertilizer base

Features

Animal manure and plant by-products comprise the bulk of organic fertilizers. Most are composted and dried before use. Application is made in dry or liquid form.

Soybeans, often used as "cover" crops, make "green fertilizer" when plowed under

Types

Some prepared organic fertilizers are applied before seeding and some during plant growth. "Green manure" consists of cover crops or weeds repeatedly plowed under. This practice, called stale seedbed cultivation, provides nitrogen and controls the growth of weeds.

Peanut meal provides a complete range of nutrients

Significance

Organic nutrients are part of the practice of sustainable agriculture, the objective of which is to grow crops without the need for chemical controls. Inter-planting and use of disease-resistant and native varieties are companion strategies.

Organics sometimes need to be supplemented with synthetic nutrients

Misconceptions

Not all organic fertilizers are completely natural; many contain synthetic or chemical ingredients approved by the U.S. Department of Agriculture. Use of organic fertilizers must be designed to meet the needs of a specific soil; soil tests are recommended before use.