Answer: Yes indeed, it's probably a pollination problem. Try hand pollinating the flowers yourself if the bees aren't helping. Take a Q-tip cotton swab and rub it against the pollen of male flowers (no little pumpkins behind the flower) and rub it into a female flower (little pumpkins behind the flower). Do this in late morning with fresh flowers only that just opened. Do it to as many flowers as you can and you should get some pumpkins from the crop.
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