what causes squash to rot fall off when small?
My squash, that is mounded as usual but in the same bed as last yr with compost amendment, begins with 3 to 4" fruit, then begins to rot shrivel up, then falls off. Is that a nutrient problem, like not enough potassium, or is it due to too much moisture? (we've had a rainy 30 days-over 20")
It sounds like you are having pollination issues. When the flowers are not properly pollinated, the plant will reject the fruit while they are just a few inches long. You may need to hand pollinate. Here is more information: https://www.gardeningknowhow.com/edible/vegetables/squash/squash-fruit-falling-off-the-plant.htm