I ventured into my garden Sunday morning and noticed that my zucchini squash plant was looking a bit wilted. Having already lost one plant in this bed to squash vine borer, I dropped to my knees and examined the stem. Horrors! Just as I suspected, the vine had an orange frass coming from it and there was a hole in the vine. I pulled out my trusty pruning sheers and carefully made a linear slice where I saw the frass. Aha! I immediately found the culprit, the destructive squash vine borer.
The next morning I was happy to see that not only was the plant happy, the three little zucchinis that had been forming had doubled in size.
The squash vine borer comes from a moth that lays it's eggs on squash plants. The eggs become the borers and as they tunnel up the stems they kill the plants. At the garden center on Saturday this was a constant topic of conversation, also at the farmer's market on Friday. One way to help prevent this damage is to spray the vines with a strong garlic spray to repel the moths. Another is to cover the plants with floating row covers as they are growing and removing it after they flower. Unfortunately, this moth cycles through a few generations in Connecticut so you are not safe once you take the cover off. A third approach is to use beneficial nematodes in late spring to kill the squash vine borer larvae in the soil before they hatch.
I have operated on my squash plants before with great success. The surest way to keep your plants healthy is to scout every day and look for that orange frass on the vines. Although the plants naturally wilt a bit in the hot late day sun, if you see them wilting even a little in the morning or on a cool cloudy day, scout some more and pull out your scalpel. It is not hard to do and totally worth it for the delicious harvest you will gain for your efforts.