Organic Pest Control

In the garden, we define “pests” as any insect, fungus, microscopic organism, plant, or animal that causes harm to our crops. Since we are not able to exclude only the detrimental elements from our gardens, we need to garden in such a way that the overall numbers and effects of these pests are reduced.

You may be surprised to discover that only three to five percent of all insects, fungi, and microorganisms are actually detrimental to the garden! The majority of the organisms we find are beneficial and their presence should be encouraged, as they provide pollination, habitat integration, natural vitality, and (detrimental) pest control. Spraying for pests, even with organic solutions, reduces the number of beneficial organisms, as well.

Preparing Your Garden

A healthy, vibrant garden is the best defense against pests. Soil that is rich in humus made from composted materials, filled with beneficial fungi, and able to hold both moisture and oxygen is the foundation of every healthy garden. The next step is choosing crops that are suited to the specific land area and growing conditions. When planting from seed, it is also especially important that the seeds are treated for resistance to common diseases. Proper plant spacing, avoiding overly wet or dry conditions, and removal of unhealthy or affected leaves, branches, or entire plants are the third step. Crop rotation is the fourth step; and cover cropping is the fifth. Increasing and maintaining beneficial insects and fungi is the final step in creating vibrant garden health and, thereby, maintaining the best pest control.

Cover Crop Considerations

Cover cropping gets less attention in general than it deserves, though increasing amounts of information has become available as research studies show definite benefits. Not only do cover crops prevent soil erosion and replace nutrients taken up by food crops, this preventative and restorative measure also provides green manure that increases humus in the soil. Some cover crops, such as mustard and oilseed radish, act as biofumigants that control soil-borne pests.

Crop Rotation

Additionally, crop rotation is probably the most time-honored method of pest control. To accomplish, the gardener should move crops to different beds every year, which prevents pests and diseases from building up and becoming problematic. In other words, you rotate the individual crops from one bed one year or growing season to a different bed the next. This method is relatively simple and efficient for the beginning or seasoned organic grower.

Plant Spacing

Highly touted methods of gardening to increase food production in small spaces, such as “square foot” gardening, do not work everywhere and can even result in an abundance of diseases and pests in some areas. Plants need to be spaced to allow for good air circulation without resulting in excessive evaporation that dries out the soil. Vertical gardening, whether on a wall or in a tower, is another method that is not practical in many areas, due to climate. The best method of increasing yield is maintaining garden health and planting the proper crop varieties for your area.

Choosing Seeds for Your Climate

You’ve probably noticed that seed catalogues offer many different types of each plant. These are the different varieties of each species, and each has its own specific preferences in the world of climate, region, and soil type. Choosing the plant species best suited to your area is a giant step forward in pest control, while choosing varieties increasingly exotic to your area will result in more pest problems. Determining the best varieties of food crops for your area is most easily done by visiting your local Farmers’ Market. Here, you can speak with local sellers to find out what species and crop varieties they’re planting and how those crops perform. They may even share some special tricks-of-the-trade, if you’re lucky! If you don’t have a local Farmers’ Market, seek out neighbors with healthy gardens or small farms, especially those farms that grow crops as CSA (Community Supported Agriculture) or an agricultural or farming cooperative, where farmers and growers of all types and experience levels pool their resources and knowledge to enable the best outcomes of the entire group.

Using Beneficial Insects

An interesting aspect of pest control that is often overlooked is attracting beneficial insects to the garden for pollination, habitat integration, natural vitality, and – specifically – for those insects that feed on pests. Flowers, both annual and perennial, are the quickest growing plants for attracting beneficial insects. You may also consider shrubs and small trees. Plants to host larvae will increase the biodiversity of your beneficial insects and help your garden thrive. You can find more information regarding plants that attract beneficial insects in this article from Permaculture News.

Bringing It All Together

Once you’ve gotten this far, the next step in pest control is inspection of your garden. Walk through each row and inspect each plant. Do not just admire the tops of the leaves, but be sure to check their undersides and inspect the stalks and branches thoroughly, as well. Look for unwanted critters, discolorations, paleness, holes, eaten edges, and other signs that may mean compromised health of the plants. Deal with any problems as quickly as possible, including removing unhealthy growth on plants and disposing of them. It’s best NOT to put these in compost if you suspect disease. If you find caterpillars or tomato hornworms, picking them off by hand is the most effective method of control. Simply drop them into a container of soapy water and they will die. Hand picking of any eggs is also highly effective.

All gardens are susceptible to pests, but a healthy garden will have fewer of them and recover more quickly.

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