Cucumber beetles

(Question)

I have a garden plot in Toronto in a community garden plot and every year fight cucumber beetles , both spotted and striped. I have tried almost everything to control their destruction. I noted a previous post re this and agree that pick and squish is most effective. Last year I put yellow and orange basins half full of soapy water amongst the zucchini and cuks and did trick some to fly into the basins and drown. Just passing this trick on. Rarely did bees fly into the basins so it did not affect the pollinators. If there are any other tricks out there, I would be delighted learn of them!

(Answer)

It sounds like you have already reviewed Ask a Master Gardener’s response to a question from last summer, Cucumber beetles, which suggests old-fashioned pick & squish (or vacuum) method.

That response also recommends planting the cukes later in the season (after the first generation of adult beetles emerge, to prevent a population rebound later in the growing season) – although this may involve seeding the plants inside, a bit more work!  Use of floating row covers, taking care to prevent bacterial wilt and rotating cukes to a new spot in the garden are also discussed in the earlier response.  Regarding bacterial wilt, note that it is important to control the early season adult beetles, as the percentage of beetles that harbour the bacterial wilt increases significantly as summer progresses.  See The Ontario Ministry of Agriculture, Food and Rural Affairs Cucumber beetles.

The University of Minnesota Extension’s Cucumber beetles in home gardens provides additional helpful information. For example, keep your garden clean and clear of debris.  The beetles over-winter as adults and enjoy the shelter provided by debris left in forgotten spots in the garden.  Remove weeds and unwanted grasses, as when the adult beetles emerge, they feast on weeds and grasses, not just the cukes you planted early in the season.

Another trick is to plant a “trap” crop of curcubits before planting the “real” cuke crop, a distance away.  The “trap” (or decoy) crop should be one that is especially attractive to the beetles, e.g., the gourd Turk’s Turban (cucumbers, gourds, melons and squash belong to the curcubit family). See Cornell University’s Vegetable MD Online, Attractiveness to Cucumber Beetles and Susceptibility to Bacterial Wilt Varies Among Cucurbit Crop Types and Varieties for ideas on other trap crops that can be used.  When the beetles show up on the trap crop, pick & squish ‘em (we don’t recommend use of chemical pesticides).   In any event, once you’ve started to see the beetles in your garden, monitor your cukes frequently.

Finally, see GardeningCalendar’s Get rid of striped, spotted cucumber beetles for lots of additional information about getting rid of these pests!

Good luck with your cucumber crop this year!