Trap Cropping in Pest Management

It may seem like madness, on the surface, to plant a trap crop in the organic farm or garden. Why would one dedicate the sweat, resources, and real estate to planting a crop that is destined to be consumed by insect pests? Shrewd organic gardeners should learn about the success that trap cropping can bring to the harvest.

What is Trap Cropping?

When organic gardeners use trap cropping to protect their vegetable plants, they plant an additional crop that lures garden pests away from the vegetables. The trap crop may be from the same plant family as the vegetable crop, or it can be an unrelated plant. The philosophy behind trap cropping is the notion that the trap crop is more appealing to the insect pest than the main crop, so insects focus their destruction on the trap crop. Therefore, a gardener doesn’t expect to harvest any vegetables from the trap crop, as it is a sacrificial crop.

Gardeners can incorporate trap crops into the garden in two ways. In perimeter trap cropping, the trap crop is planted in a border that surrounds the desired vegetable crop. This is useful for organic farmers, who plant a large field with one cash crop that is vulnerable to pest attack from every border. Home vegetable gardeners can experiment with row intercropping, which alternates a row of the trap crop with a row of vegetables.

Advantages of Planting a Trap Crop

When combined with other organic pest control methods, trap cropping can reduce or eliminate the need for spraying, even the need for organic bug sprays. Trap cropping facilitates the beneficial insect population, because it maintains the insect population that attracts beneficial insects. In some cases, trap cropping can serve a dual function as a soil improvement method; because some trap crops, such as alfalfa and legumes also act like green manures.

Succeeding With Trap Cropping

Before installing a trap crop, gardeners must positively identify the pest of concern. Trap crops don’t reduce plant diseases, and many trap crops only work against one or two kinds of insect pests.

Gardeners must choose a trap crop that is more appealing to the insect than the desired vegetable crop. Gardeners and farmers may consult their local county extension program for guidance on this matter.

A trap crop shouldn’t serve as an everlasting buffet or insect pest nursery. Once the insect population is at its peak, gardeners must remove or otherwise destroy the trap crop to prevent the insects from producing future generations of pests.

Trap Cropping Examples

Garlic aficionados can plant a border of marigolds to control thrips. Cabbage growers can add a row of mustard to draw flea hoppers, webworms, and aphids away from their crop. Slugs relish chervil over most any other vegetable or ornamental, so add clusters of chervil between desired plants. Finally, the Colorado potato beetle prefers tansy over its namesake potato crop.

Source:

Online Information Service for Non-Chemical Pest Management in the Tropics