The paradox is that the last week of June is not considered “early” on most gardening calendars. In fact, many gardeners will smile as they think of the leafy summer squash and pumpkin plants growing, even blooming, in their gardens, and Bob has just planted his squash seeds and won’t be picking his “early” squash until August.
But I have reason for my apparent madness. By planting squash late I’ll avoid a problem I used to have every year—collapsed, dying squash plants, victims of the squash vine borer.
By about July 1, most of the squash vine borer moths, which you might mistake for wasps, here in Central Maryland have laid their eggs at the base of susceptible plants, which include summer and winter squash and pumpkin. Since my squash will be poking through the soil about July 1, I hope to avoid the egg-laying females and then the larvae that kill squash plants by boring into the stems.
“If there are no sizable plants in your garden when the adult squash vine borers emerge from cocoons and mate, you should not have a squash vine borer problem,” explained Jon Traunfeld, University of Maryland Extension Specialist for veggies and fruits. “Planting summer and winter squash and pumpkin seed directly in mid-June in Central Maryland or setting out transplants in mid-June can help you avoid the problem.”
Traunfeld said that late planting is not the only solution. Alternative remedies include wrapping stems with aluminum foil and using floating row covers early in the season before the squash flowers. He urges gardeners to check out the Home and Garden Information Center website’s Diagnostics page about the Squash Vine Borer, which includes key information plus photographs of a squash plant wilting after borer infestation, the adult moth, and a larva inside a squash stem.
If you’ve had squash vine borer problems last year, chances are excellent that you’ll have them again this year. So plan ahead and plant another hill or two of squash this week or next. You too can outwit the squash vine borer.
Here’s a link to the HGIC page with photos of the squash vine borer: http://plantdiagnostics.umd.edu/level3.cfm?causeID=425