My squash plants wilt and die just as they start producing
Sudden wilt with a hole and sawdust-like frass at the base of the stem is vine borer. Gradual yellowing with grey bugs underneath is squash bug. The timing of your cover is the whole game for the first one.
What actually works
Cover from transplant, **remove the moment it flowers** or nothing gets pollinated. That window excludes the borer moth during her egg-laying period and costs a few dollars of fabric.
A planting that goes in after the borer's flight period dodges it entirely. Cheap insurance and it extends the harvest anyway.
Slit the stem lengthwise, remove the grub, bury the node in soil to re-root. It genuinely works sometimes, and it's a pleasant evening's work if you only have six plants.
Bronze egg clusters on the undersides of leaves. Two minutes a plant, twice a week, beats every spray — and the adults are nearly impossible to kill once established.
Borers largely spare **Cucurbita moschata** — butternut, Seminole, tromboncino — because of their solid stems. If borers beat you every year, change the species rather than the tactics.
Also searched as
squash vine borer · squash bugs · zucchini wilting · pumpkin plant died · hole in squash stem · sawdust at base of squash · cucumber beetles