Extension News: Protecting your cucurbits
They may not bear a family resemblance, but cucumbers and pumpkins are closely related. They are cucurbits, a family that includes other popular garden plants such as zucchini, summer squash, winter squash, cantaloupe and watermelons. They all tend to take up a lot of room in the garden, so if you’re going to dedicate that much space you’ll want to reap as much fruit as you can. Yes, botanically, these are fruits, though we include many of them in our meals as vegetables.
The problem with cucurbits is that we’re not the only ones who enjoy them. Between insect pests and bacteria, plants in this family attract a lot of troublemakers. Striped and spotted cucumber beetles are the most common insect pests on all the cucurbits and will cause significant damage to seedlings and ripening fruit. They also transmit the bacterium that causes bacterial wilt, which hits cucumbers and melons particularly hard. Gardeners can be taken by surprise when wilt attacks; in the morning the plant can look healthy, but by evening a runner and its leaves have wilted irretrievably.
The best time to manage this problem is immediately after planting by applying a one-time soil drench of a systemic insecticide, which should provide three to five weeks of control. But if you didn’t apply the insecticide at planting, it’s still worth your time to scout for beetles and apply foliar insecticides as necessary to protect susceptible plants, particularly close to harvest. If you only have a few plants in your garden, picking off beetles by hand is another option, though you may have to do it daily, and it’s not a guarantee against wilt.
Squash beetle is a large lady beetle with 12 black spots on its back and an orange thorax. Whereas some lady beetles are beneficial and feed on pests like aphids, the squash beetle feeds on the underside of leaves, skeletonizing them, and can be a serious pest of squash and pumpkin. Apply foliar insecticides as necessary during the mid- and late season.
Then there’s the squash bug, which is brown and about 1-inch in length. They appear starting in June. They damage plants by dining on the sap, as well as causing leaves to wilt and collapse. Most detrimental, though, is that they carry the bacterium for yellow vine decline, which affects melons, watermelon and pumpkins. Foliar sprays targeting newly hatched nymphs are more effective than sprays used against the later stages of the insect. You may need to spray multiple times throughout the course of the growing season.
Keeping your cucumbers from having direct contact with the soil can prevent belly rot. When a cucumber lies directly on the soil, it can develop tan or brown lesions that resemble a dry rot. Using mulch as a barrier between fruit and soil helps. Also be careful not to overwater; overly wet soils can add to the problem.
With a little care, your homegrown cucumbers, squash and melons will thrive and give you a bountiful harvest and enrich your table.
For more information about cucurbit diseases and pests, check out the University of Kentucky Cooperative Extension publication, ID-128, Home Vegetable Gardening, http://www2.ca.uky.edu/agcomm/pubs/id/id128/id128.pdf, or contact the Butler County office of the University of Kentucky Cooperative Extension Service.
Educational programs of the Cooperative Extension Service serve all people regardless of economic or social status and will not discriminate on the basis of race, color, ethnic origin, national origin, creed, religion, political belief, sex, sexual orientation, gender identity, gender expressions, pregnancy, marital status, genetic information, age, veteran status, or physical or mental disability.
By: Greg Drake II, County Extension Agent for Agriculture and Natural Resources
Source: Ric Bessin, extension professor, UK Department of Entomology