Cucumber Beetle

Cucumber beetles are more dangerous to their cucumber family hosts than many pests because they transmit deadly diseases: mosaic and bacterial wilts.

Don't be confused by the two different forms of this pest. The striped form is shown at right. Its cousin features a dozen black spots. But whether spotted or striped, both are the same size (about .25" long) and the same, greenish-yellow color. Both dine on a wide variety of cucumber-family vegetables (cucumbers, squash, zucchini), as well as various ornamentals, such as roses and dahlias. Another well-known family member is the corn rootworm.

The adults overwinter in weeds and plant debris. They emerge in spring after the last frost and enter gardens once the growing season is underway. You may first notice them inside squash flowers. They lay orange eggs at the base of host plants; white larva with legs and brown heads chew on roots. Short, northern seasons allow just one generation a year. In the south and mild west, two or more generations are typical.

Insect Netting With Hoops

• When buying seeds or plants, choose varieties of cucumbers and squash that are resistant to cucumber beetles.
• Cover young plants with garden fabric, or protect a row of plants with a new type of row cover: Insect Netting with Hoops. The finely-woven, polyethylene row cover has built-in supports, so it's easy to install.
• Knock, shake, or hand-pick beetles off plants and out of flowers and dispose of them. Cucumber beetles can fly, so they're tricky to catch.
• Dust plants and flowers with Garden Dust.
• Apply beneficial nematodes to soil to control larvae.
• Clean up debris in the fall to prevent overwintering pests.

Still have questions?: Ask our in-house gardening experts.