Cucumber Beetle
Quarter-inch yellow beetles with black stripes or spots, on cucurbit seedlings almost the day they emerge. Beyond the chewed leaves and scarred fruit, they spread bacterial wilt as they feed — a vine that wilts by noon and dies in a week was likely their work.
Pest checklist
Four things to look for. If most of them match what you are holding, you are in the right place.
What gets rid of them
Gentlest option first. For most backyard cases the first one is enough, so try these in order and stop as soon as it works. If you do spray something, the product label tells you how — please read the notice further down.
1Row cover until flowering
Protects the vulnerable seedling weeks; lift covers at bloom so the bees can work.
floating row cover gardenTry this first2Yellow sticky traps
Intercepts adults moving into the patch; place at plant height along the row edge.
yellow sticky traps garden3Straw mulch and late planting
Mulch slows beetle movement to stems; a second sowing in mid-June often misses the spring flush entirely.
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Which plants get cucumber beetle
Every plant we cover that gets cucumber beetle, grouped by type — tap any one to open its page. A note beside a plant came from that plant’s own entry, because the same pest can be a minor nuisance on one plant and a serious problem on another. Plenty of plants we do not cover get it too.
Plant families hit hardest
Related plants often share the same problems, so if one plant in a family has it, check the others. The largest group here is Cucurbitaceae, with 5 of the 6 affected plants.
- Cucurbitaceae5 plants
When to treat
Treat as soon as you see them. They spread bacterial wilt while they feed, so a few early beetles matter more than the chewing suggests.
Timing only — the label is the law
This page tells you when to watch for cucumber beetle and when treating is worth considering. It is not a recommendation to apply any particular product. Read and follow the product label before you spray — under federal law the label is the legal instruction, and using a pesticide against it is illegal.
- Check the pre-harvest interval. Every product that’s cleared for an edible crop sets a minimum number of days between spraying and picking. Find it on the label before you spray anything you intend to eat.
- Check the re-entry interval before you or anyone else works in the treated area again, and use the protective equipment the label names.
- Confirm the product is registered for your crop in your state. This page groups many different crops together, and a product legal on one of them is not legal on all of them — state registrations differ too. Your state pesticide agency or local extension office can confirm both.
- Rates and mixing instructions come from the label, never from us. We don’t publish them because they differ by product and formulation.
Other problems on the same plants
If a plant gets cucumber beetle, these are the problems it most often gets as well, so they are worth checking for while you are out there. They tend to appear together; one does not cause another.