Answer: You definitely want to pick off most of the flowers. Growing larger pumpkins depends primarily on the specific variety you planted. To maximize the size within the expected range, allow the vine to put on some size prior to setting fruit by removing the first female flowers, that way it will have proportionately more foliage for photosynthesis. Once you have allowed a pumpkin to set, remove subsequent blooms. Allow the vine ample space, as a rule of thumb 150 square feet. Water deeply during dry spells. Top dress with good quality compost (ideally you would have worked in compost and well rotted manure prior to planting.) You may also want to fertilize every three to four weeks with a granular fertilizer spread around the root area to keep fertility high. Ideally this would be done on the basis of soil tests, but a rough estimate might be a half cup of 10-10-10 per plant. Be vigilant in controlling pests such as cucumber beetles, squash bugs and borers. Good luck!
If you are thinking about trying to grow award winning giant pumpkins, here are some tips on doing that. You may need to cut and paste the complete url into your browser to make it work correctly.
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