I have searched for and read several earlier threads about zucchini problems. My two zucchini plants put on fruit, but after growing to lengths of around 3-4", they shriveled up and died. From what I have read it sounds like the problem is a lack of bees to pollinate the plants. I did not, however, read the exact method of hand pollinating the zucchini. I understand you take a male flower, which is located on a fruitless stem, and rub it against a female flower, which is the flower on the end of a fruit. Assuming that is correct, my question then is do I open the female flower to pollinate? The flowers on the ends of my zucchini are closed. I tried rubbing the male flower on a closed female flower and I tried rubbing the male flower on a female flower that I opened manually. Neither appears to have worked. I may have been too late or else my technique needs improving. Also, how soon should I pollinate the female flowers? As soon as they are first formed or should I wait until they grow to a couple of inches long?
If it makes any difference in identifying my zucchini problem, I have cucumbers planted in the same box of my Square Foot Garden and they have done very well. That's one of the reasons I ruled out soil related problems.