Watch Out for Squash Bugs: Common Garden Pest Threatens Summer Crops

Watch Out for Squash Bugs: Common Garden Pest Threatens Summer Crops

By Jessica Strickland, Wayne County Horticulture Extension Agent

As summer approaches and gardens begin to thrive, many North Carolina gardeners eagerly anticipate harvesting fresh squash. But along with the joys of growing zucchini, pumpkins, and squash come some unwelcome visitors—squash bugs.

Squash bugs are among the most common and destructive pests in home gardens this time of year. These insects not only damage plants but can significantly reduce yields and even kill plants if left unchecked.

Understanding the Enemy

The squash bug (Anasa tristis) overwinters in protected areas, such as under plant debris, and emerges in the spring looking for squash plants to feed on. Females lay clusters of around 20 bronze or copper-colored eggs, usually on the undersides of leaves or along the stems. These eggs hatch in one to two weeks—typically from mid-May to mid-June—and nymphs soon begin feeding on plant sap.

Young squash bugs start with black heads and legs and light green bodies. As they mature, they become light gray and eventually develop into brownish-black adults about 5/8 inch long. Their piercing-sucking mouthparts extract nutrients from the plant, causing yellow spots, leaf wilting, and ultimately plant death if infestations go untreated.

Control Strategies: Prevention and Action

Effective squash bug control involves both prevention and active management. Jessica Strickland, Horticulture Extension Agent for North Carolina Cooperative Extension in Wayne County, offers the following advice:

  • Fall Cleanup: Remove plant debris where squash bugs may overwinter.
  • Mulch Management: Consider removing mulch if bug populations are high, as it provides shelter.
  • Healthy Plants: Keep plants well-watered and properly spaced to help them withstand insect stress.
  • Early Control: Young squash plants are more vulnerable, and bugs are easier to eliminate when immature.
  • Frequent Scouting: Check plants regularly, handpick bugs, and crush egg masses found under leaves.
  • DIY Traps: Use boards or newspapers as traps; bugs will hide under them overnight, making removal easy in the morning.
  • Soapy Water: Simply knocking bugs into a bucket of soapy water is an effective, chemical-free method.
  • Row Covers: Use early in the season to create a physical barrier between bugs and young plants.
  • Early Planting: Planting squash in early April may help you harvest before bug populations peak—just be ready to protect against late frosts.
  • Insecticides: When necessary, use insecticides targeting young nymphs. Apply in early morning or late evening to avoid harming pollinators. Recommended active ingredients include permethrin, acetamiprid, spinosad, and malathion.

Strickland reminds gardeners that using insecticides responsibly means reading labels carefully and ensuring compliance with all current regulations.

More Help for Gardeners

The Wayne County Extension Master Gardener Volunteer Plant Clinic is open Mondays, Wednesdays, and Fridays from 10 a.m. to 1 p.m. (March through June) to answer your gardening questions. You can call 919-731-1433, email [email protected], or visit the office at The Maxwell Center, 3114-B Wayne Memorial Drive, Goldsboro.

Stay up to date with local gardening tips by signing up for the Wayne County Extension Gardening email list at wayne.ces.ncsu.edu/email-me. You can also follow updates on Facebook @waynecooperativeextension and Instagram @waynecountyextension.

Need plant inspiration? Visit the NC Extension Gardener Plant Toolbox at https://plants.ces.ncsu.edu.

With vigilance and good garden practices, squash bugs don’t have to ruin your summer harvest.

Share

Events

W.I.S.E. Meet Up