Answer: Check the seed catalogue or the nursery catalogue where you purchased the seed for the days to harvest of each variety. Pumpkins can take a long time, most falling in the 80 to 120 day range. The BIG ones usually take longer than the others. I would aim to have them ripen in late September. Pumpkins will keep, and this way you won't be too late should something delay harvest. Early June would probably be about right for most pumpkins in your area, but a bit too late for the "giants".
To get really large fruits, build the best soil you can with lots of compost and manure, give them all the water they want, and keep leaf diseases in control. Anything that reduces leaf area cuts down on carbohydrate production and pumpkin size will be reduced. Remove all fruit on a vine except one and watch it grow. Place a piece of plywood under it to keep it off the soil and away from pests that may burrow into the skin. Then begin to practice your 1st prize acceptance speech at the county fair! If you want to pursue this in earnest, there's a book on the subject - "How to Grow World-Class Giant Pumpkins", by Don Langevin (Annedawn Publishing, PO Box 247, Norton, MA 02766; ISBN#
0-9632793-4-3). Good luck!
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