Want to grow a giant pumpkin?
Here's how: Purchase "ATLANTIC GIANT" seed. Several catalogs offer this variety.
Climate is important, warm but not hot. The ideal is 75 - 85 degree day temperature. Plants have large leaves and lose water faster than roots can pull it up. Start seed inside and plant out in
April or May. Protect them from night frost. Set plants in the soil 20 - 25 feet apart. Use some type of cover for the first 2 weeks. Rototill in some aged cow manure or some chemically complete fertilizer.
After plants start to vine and produce side shoots, male flowers appear first. Watch daily for first female blossoms. The blossoms need to be hand pollinated. Wait for the second or third blossom to pollinate. Early in the morning select a female blossom that has not opened but is beginning to show color. With masking tape, tape the blossom shut around the tip to keep insects out. The next morning remove the tape and brush the stigma of the female flower with the stamen of a male flower and re-tape the blossom. Tie a price of bright yarn around the stem by this flower so you can find it later.
Check the stem of the growing fruit to make sure it is well attached to the vine as the fruit can tear itself off the vine. Leave only 2 - 3 fruit on each plant. When they reach softball size remove all others and begin to prune the vines. At 20 feet, pinch off the vine tips. The side shoots must also be pruned at 6 - 8 feet. Break off all other female flowers. Water twice a week (15-20 gallons). Keep leaves dry. Keep fruit from crushing vines. Pull vines free of soil if they start to root by a fruit. (Rooting in other places is OK).
Measure fruit each day. They do most of their growing during the night. At half size they gain 10 - 15 pounds per day and can add 2 inches in circumference a night. Some growers use calcium nitrate as a side-dressing and water it in. Nearing September and harvest, growth slows down to less than 1/2 inch in girth per day. They can collapse or explode from stress at this time.
Also check out ...
UC websites for the Vegetable Research and Information Center (http://vric.ucdavis.edu) and Integrated Pest Management (www.IPM.ucdavis.edu).