One small seed produces the gigantic pumpkins entered in competitions around the world, including the 2021 record 2,703-pounder that weighed almost as much as a Volkswagen Beetle.
Maybe you won’t grow one quite that size, but plant Dill’s Atlantic Giant and you can grow a whopping pumpkin, says Jim Myers, a vegetable breeder for Oregon State University.
“I’ve had these types growing in fields, and without doing anything special to them, I’ve gotten 400-pounders,” Jim says. “They certainly need plenty of water and lots of space to grow.”
Modern monster pumpkin genetics go back to grower Howard Dill—a Nova Scotian farmer who spent 30 years selectively breeding giant pumpkins. He came up with Dill’s Atlantic Giant, and every world champion since has come from offspring of those seeds.
Howard reinvigorated giant-pumpkin competitions in 1978. That year, he broke a 75-year-old record. His champion 438.5-pound pumpkin held the world record four years straight. Howard landed in the Guinness World Records book in 1981 with a 493.5-pounder.
To grow a monster pumpkin takes a monster amount of land, water and fertilizer. If you would like to try, Jim offers the following advice:
Use Dill’s Atlantic Giant seeds.
Germinate monster pumpkin seeds at air temperatures of 65 to 75 degrees and soil temperatures of 70 to 90 degrees.
Grow pumpkins indoors from seed and move the starts to your garden about five to seven weeks later. Plant the beginning of June or after the last frost.
Grow in full sun.
Avoid compacting soil in the field. Some growers use stepping stones or boards to minimize impact during the season.
Place plastic around the base of the pumpkin two weeks before planting to bring the soil temperature to about 60 degrees. A high tunnel or hoop house also can be used—especially during the early part of the season—to create a warmer environment for the plant.
Provide your pumpkin with plenty of room to spread. A single plant may use roughly a 40-foot diameter circle.
Remove enough flowers and fruit—pumpkins are actually fruits—to force the plant to put all its energy into producing one behemoth fruit.
Hand-pollinate pumpkins to increase the number of seeds that develop and the likelihood for bigger fruits. Pull off the petals of male flowers, which look like straight stalks, and dab these on the female flowers, which have little round ball-shaped ovaries at their base.
Give pumpkins 130 days or more to mature.
Check soil daily. The ground always needs to be evenly moist, but not soggy. Keep water off foliage to discourage disease.
Apply aged manure in fall, or in spring put down compost—up to 5 cubic yards per plant. Then use a fertilizer periodically through the season. Apply lime in fall to bring soil to a more neutral pH if a test determines it is on the acidic side. Fertilize every two weeks or so with decomposed manure, compost or fertilizer.
Maintain a weed-free area around plants.
Stake down or bury leaf nodes along the vine. These will root and help prevent wind from rolling the vines.
Place the growing pumpkin on a large piece of cardboard or piece of wood to repel soil-dwelling insects.
As the fruit gains size, shade it to prevent scalding and reduce overheating. The skin will remain more flexible and less likely to split.
Harvest your pumpkin just before the first frost. It won’t color to the bright orange of a jack-o’-lantern, but will be pale yellow to orangish red when it is ready.
At harvest time, be careful to avoid cracking the pumpkin, which will disqualify you in competitions.
After you have entered your pumpkin in weigh-off competitions, you might be able to sell it. Casinos or restaurants will sometimes buy a champion and contract with a professional carver to create a short-lived sculpture.
You can roast the seeds, but be forewarned: The flesh is not very palatable.
“It’s something that’s interesting to do,” Jim says. “There’s not a lot of practicality. There might be a little prize money and it’s good for notoriety.”