Only the first year that I planted squash did I not battle squash borer. Each summer I get only a few squash before the borers invade and kill the plant. I've tried the aluminum foil around the base of the plant, I've stirred boric powder into the soil and still can't keep them from getting the plants. Sprays are ineffective as well. Do you have any solid suggestion for prevention?
Prevent Squash Borers
Certified GKH Gardening Expert
It sounds like you may need to rotate your squash plants (i.e. move them to another location). Planting them in the same area year after year makes the plants more prone to these types of attacks, making treatment of the problem more difficult. Other than that, the best treatment I have found is to start treating your vining plants in the spring with an organic pesticide called neem oil. It is people and beneficial bug safe and is absorbed by the plant, killing the vine borers inside. You need to apply it weekly to the plants and is the best treatment I have seen for them.