How to Control the Squash Beetle Bug

Overview

The squash beetle bug is one of the most significant pests of the squash plant. They damage plants by feeding on the plant's juices and occasionally the fruit. Damage is first seen by a yellowing or darkening of the leaves, followed by wilting. Squash bugs are shield-shaped and gray, brown or black. They produce an offensive odor whem smashed. Adults overwinter in garden debris, and then emerge in the spring where they lay eggs to produce the next generation. The eggs are orange and yellow and are often seen in groups on the undersides of the leaves. The nymphs, or babies, are orange or red.

Step 1

Look over every squash plant carefully and check for squash bug eggs. This can be done at anytime during the day. When you see a group of eggs, simply smash them between your fingers by rubbing them against the leaf surface. Be sure all eggs are smashed.

Step 2

Spray a stream of water around the bottom of the squash plants to flush out the adult squash bugs from the bottom of the plant. As they attempt to get to higher ground, grab the adults and place in a jar of water with 1 tsp. of dish soap added to the water where they will quickly drown.

Step 3

Sprinkle pyrethrum powder around the base of the squash plants in the evening when the blooms are closed and bees are no longer working the flowers. Pyrethrum powder is highly toxic to bees, and since you need the bees to pollinate the squash plants to produce squash, use caution when spreading.

Step 4

Place a 1-by-6-inch board of at least 1-foot long by each squash plant. The adult bugs will get under the board in the evening and in the heat of the day for protection. After 24 hours, lift the board and sprinkle the exposed squash bugs with pyrethrum powder.

Step 5

Clear all garden debris from the garden and around the garden in the fall so squash bugs do not have a place to hide during the winter. Look for old boards, flowerpots and dead plant material that can provide a shelter for the squash bug.

Things You'll Need

  • 1-by-6-inch board
  • Source of water
  • Pyrethrum powder
  • Jar
  • Dish soap

References

  • University of Minnesota Vegetable IPM Resource: Squash Bug
  • National Sustainable Agriculture Service: Squash Bug and Squash Vine Borer: Organic Controls
  • Virginia Tech Extension: Squash Bug
  • Colorado State University: Some Pesticides Permitted in Organic Gardening
Keywords: squash bug pests, exterminating squash beetles, squash pests

About this Author

Based in Rockdale Texas, Jim Gober has been writing garden-related articles for 25 years. His articles appear in several Texas newspapers including The Rockdale Reporter, The Lexington Leader, The Cameron Herald and The Hearne Democrat. He is a Master Gardener and Certified Texas Nursery and Landscape Professional. He holds bachelor degrees in English Writing from St. Edward's University and Finance from Lamar University.