Last year, my cucumbers were attacked by cucumber beetles and they all died. I was wondering if I should stop growing cucumbers this year. Are there any ways to prevent this problem from happening ahead of the planting season?
Are there any specific pesticide I could use?
Thanks so much for your help.
Thank you for contacting the Toronto Master Gardeners. We share your distress caused by the very colourful but so damaging cucumber beetle. Their lethal damage to cucumbers is primarily through the transmission of bacterial wilt disease (Erwinia tracheiphila). Some information from a previous Toronto Master Gardener post speaks to management strategies “…You can order Cucumber Beetles lures and traps, which attract the adults so that you can then dispose of them. You can also use the “pick and squish” method, early in the evening, which although messy, is most effective. If there are large numbers, you can swoop them up with a portable vacuum. The Ontario Ministry of Agriculture, Food and Rural Affairs recommends that method most strongly.
Next year, you might also consider planting your cucumbers later in the season. The first generation of adult beetles (generally the most damaging) emerge in mid-June to early July. If you seed your cucumbers indoors and transplant them into the garden in mid- or late July, you may avoid the problem. Consider also, using floating row covers over the young seedlings, which must be removed when the plants flower to allow for pollination.” Information on this blog post speaks to the use of bacterial wilt-resistant varieties https://savvygardening.com/cucumber-plant-problems/
As Master Gardeners we attempt to avoid the use of insecticides. However more information about crop pest treatment in Ontario can be found here http://www.omafra.gov.on.ca/english/crops/pub838/pub838.pdf.
Other management practices to deter cucumber beetles and prevent the spread of bacterial wilt include disposing of infected plant material in the garbage and not your garden compost. Rotate cucumber plants to a new area of the garden each season – try to leave 3-4 years between the use of the same space if possible. There are good compact, container-friendly cucumber varieties available if you feel you want to give the garden soil a break and grow in pots for a season or two.
Best of luck this growing season!