Grasshopper Pest Control in an Organic Garden

Stop Grasshoppers with Nematodes, Trap Crops, and Cultural Controls

Jul 13, 2009

Grasshoppers are common garden pests in the summer months, feeding on flower and vegetable gardens. Use organic and natural pest control methods to stop these insects.

Although there are several hundred grasshopper species, not all of them are farm and garden pests. If a gardener notes the presence of adult grasshoppers in the garden, and observes accompanying defoliation of vegetable and ornamental plants, he can implement several organic pest control methods to control grasshoppers.

Grasshopper Predators and Parasites

Robber flies and spiders prey on grasshoppers, and gardeners can encourage their populations by eliminating the use of chemical pesticides. Domestic poultry such as chickens and ducks feast on grasshoppers, so rural gardeners can weigh the benefit of grasshopper control against the drawback of plant damage from these birds.

Early in the season, gardeners have a control option in the form of a protozoan packaged in bran flake bait. The Nosema locustae is a disease that causes death of young grasshoppers over the course of the growing season. This bait is especially popular with organic farmers attempting to control grasshopper infestations in a monoculture.

Grasshopper Barriers

Grasshoppers can chew through fabric row covers and other flimsy barriers, but aluminum screening will stop adult grasshoppers from accessing plants. It’s impractical to cover the entire garden with this screening, but gardeners trying to establish new shrubs or trees may protect individual plants with the screen during the first season, when plants are vulnerable to permanent stunting damage.

Trap Crops

For gardeners who live beside farmland or pasture, the battle with grasshoppers will be a yearly one. Gardeners can plant a trap crop row between the field and the garden to lure grasshoppers away from flowers and vegetables. Grasshoppers like zinnias, so plant a row of these along the edge of the property. For added control, plant a row of cilantro between the zinnia trap crop and the garden, as this pungent green repels grasshoppers.

Cultural Control

Practicing good garden hygiene is helpful in establishing long term control of grasshopper populations. Weedy areas and dead brush provide a habitat for grasshoppers to lay their eggs, so gardeners should mow or trim any fencerows or ditches that support the next generation of insects. Remove dead crops or spent annual flowers at the end of the season, and trim back perennial plants after the first frost.

Organic gardeners can accomplish grasshopper control and soil enrichment at the same time by planting a cover crop. Grasshoppers reject peas and sweet clover, but these cover crops fix nitrogen in the soil, adding to its fertility. In areas with previous grasshopper infestations, it’s worth planting an early crop for one season and finishing the season with a cover crop to discourage grasshoppers. Gardeners can plant peas, spinach, lettuce, and broccoli in the spring, and forgo late summer plantings of sunflowers, corn, or dry beans that attract egg-laying female grasshoppers.

The copyright of the article Grasshopper Pest Control in an Organic Garden in Organic Gardens is owned by Jamie McIntosh. Permission to republish Grasshopper Pest Control in an Organic Garden in print or online must be granted by the author in writing.