Organic food is popular because it is grown using a sustainable land management system that improves the surrounding environment. Using organic inputs without insecticides, herbicides or commercial fertilizers, organic production reduces pesticide exposure to humans, groundwater and the environment.
In a backyard garden, growing food organically without pesticides can help preserve beneficial insects living in and around the garden. Ladybugs, lacewings, predatory mites and wasps and many other beneficial insects can be helpful against insects that damage vegetable crops. Ladybugs feed on aphids, which feed on plants and certain kinds of wasps feed on tomato horn-worms, which eat through tomatoes.
Crop rotation, trap crops and using vegetable cultivars with resistance to certain insects and diseases are also important tools for controlling pest problems organically. Organic or “soft” insecticides such as horticultural oils also can be used in an organic system.
Row covers are another tool organic gardeners can use to protect plants from insect damage. This fine-spun, polyester fabric creates a physical barrier around plants, while allowing sunlight and water to get through. Row covers are particularly useful on plants that don’t require pollenation, such as lettuce, cabbage, carrots or potatoes. Only the leaves or roots of these plants are harvested, not the fruits.
The first thing to consider when starting an organic garden is the soil. Organic doesn’t just mean no pesticides - it also means not using any type of commercial fertilizer, so nutrients must be provided through other sources. Organic matter, cover crops that fix atmospheric nitrogen and manure are examples of soil amendments that can provide nutrients and improve soil structure. Cover crops, such as red clover, are grown in the garden then tilled back into the soil to improve soil fertility and drainage and increase beneficial insect habitat. When using manure, make sure the animals have not been fed or treated with antibiotics or other products that are not organic. The garden won’t truly be organic if the manure isn’t organic.
The most important part of an organic garden is the soil. Spring is a great time to plant cover crops for a new organic garden, and fall is the ideal time to begin improving soil. Manure and organic matter added in fall will begin to break down over the winter. By spring, the soil will be ready and planting can begin.
For the home gardener, some of the best plants to grow organically are tomatoes, lettuce, cabbage and carrots.
For more information about the standards for organically grown foods, visit the National Organic Program web site at http://www.ams.usda.gov/nop/indexIE.htm.
Source: Sarah Browning, University of Nebraska–Lincoln
