Organic Pest Control: Using Trap Crops to Protect Your Vegetable Garden

Gardeners are generous — sharing seeds, plants, harvests. But generosity ends with pest insects. Few things madden more than bugs devouring lovingly tended vegetables. Season's end is perfect for reflecting on successes, problems, and how to grow healthier next year.

One organic technique controls pests without sprays: trap cropping. A pest attracted to a particular plant is lured away by an even more appetizing decoy. The insect ignores the main crop for the trap crop, which is then hand-picked or destroyed.

"Trap cropping is a form of companion planting," says Jessica Walliser, author of Attracting Beneficial Bugs to Your Garden. "The idea isn't to repel insects, but to attract them to sacrificial plants, keeping them away from what you want to harvest."

If you'd like to try trap cropping, follow these guidelines:

• Only use a trap crop if you've had a destructive pest previously.
• Don't use it as a precaution — you may invite new pests!

Farmers plant trap crops on field perimeters. In home gardens, Walliser recommends planting at least 10 feet from the main crop. Here are specific crop-pest-trap crop combinations:

Tomatoes

Pest: Leaf-footed bugs (Leptoglossus phyllopus)
Trap Crop: Black oil sunflowers (also attract birds that eat seeds and pests)

Squash

Pests: Squash bugs (Anasa genus) and squash vine borers (Melittia cucurbitae)
Victims: Squash (especially butternut, summer), cantaloupe, watermelon
Trap Crop: More squash, especially blue hubbard. Plant two weeks before main crop for a head start.

Cucumbers, Cantaloupe, Watermelon, Squash, Pumpkins, Gourds

Pest: Cucumber beetles (Diabrotica and Acalymma genera) — they transmit bacterial wilt, which kills plants.
Trap Crops: Amaranth, blue hubbard squash, zucchini

Apples, Peaches, Tomatoes, Peppers, Corn

Pest: Stink bugs (many Hemiptera species)
Trap Crops: Black oil sunflowers, amaranth, buckwheat

Keys to Success

Keep trap crops healthy so they remain appealing; pests will move to your main crop if the trap crop declines. Remove and destroy insects and eggs as you see them — don't wait for populations to build. Trap crops don't work on all insects and should be part of a broader organic strategy: diverse crops, pest-resistant varieties, crop rotation, beneficial insects, cover crops.