Every year around June, we get questions in the office about one of the most feared enemies of the vegetable garden. Troublesome and unsightly squash bugs are known to suck the juice from the fruits they attack, destroying the harvest.
Additionally, they appear on squash and all vegetables even remotely related to squash and gourd. They are almost impossible to combat if you don’t do it at the right time. So, what can you do to combat them? Are there methods to put these enemies in their place?
The key to effective squash bug control lies in the early stages, with mitigation and a strategic approach to your garden. One of the most powerful tools you have at your disposal is crop rotation.
By moving your tender vegetables to a different area each year, you can actively exclude newly growing plants from any remaining pests that may have been carried over in the soil or plant debris. This simple but effective practice can significantly reduce the risk of a serious infestation.
Elsewhere, looking for pests from the start will be your saving grace. Squash bugs lay their hard, burgundy eggs in staggered rows along the underside of plant leaves. If you look for them early, you can try smashing them or picking them off and then throw them away in soapy water. However, in many cases you will find that the eggs are too hard to smash or too stuck to remove.
In this case, it is recommended to cut away that part of the leaf and then throw it in soapy water. While it may not be pretty, the uninfected leaf still has enough surface area to photosynthesize and adequately nourish the plant.
From this point on, you will need to actively manage an infestation as the eggs hatch and the nymphs feed. If you are willing to go that route, this is the best time to treat the plants with a pesticide as the nymphs have not yet developed a hard protective exoskeleton.
Place some sort of cover on the ground, such as a board, tile, or piece of cardboard. This is where the insects gather in the early morning in search of warmth. This makes it easier to locate them for a spray treatment. You want to use a product with the active ingredient spinosad, permethrin, cyhalothrin, or cyfluthrin. For proper and safe application, follow the label instructions carefully.
You can choose to avoid a chemical route. Although not as effective, lifting the ground cover in the morning allows you to hand pick the pests and drop them into soapy water. This is usually more effective with a flexible cover, such as cardboard. With the insects clinging to it, the cardboard can be folded and the insects can be funneled into the water, allowing them to disperse as they are captured. If you do this early, you can practice this several times in the morning before the heat of the sun arrives.
Anthony Reardon is a horticulture agent with Kansas State University Research and Extension. Need help? Contact Johnson County Extension’s gardening hotline at 913-715-7050 or email garden.help@jocogov.org.
