He promised his sick mother he would cultivate giant pumpkins. Now he's an award-winning grower.

It was another successful pumpkin season for the Brandon, Wisc., farmer who grew a 2,000-pound giant pumpkin last year and took first prize at the River Prairie Ginormous Pumpkin Festival in Altoona, Wisc., near Eau Claire.

In fact, Tom Montsma's largest pumpkin this year was over 300 pounds larger, weighing in at 2,360 pounds and breaking his personal record.

This was enough for Montsma to take third place at the Stillwater Harvest Fest giant pumpkin weigh-off in Stillwater, Minn. on Oct. 14.

The Stillwater weigh-off was historic, Montsma said, because the top-10 largest pumpkins in the competition set the record for the highest top-10 average weight at a giant pumpkin competition, with an average weight of 2,136 pounds.

The winner of the weigh-off was Charlie Bernstrom of Lancaster, Minn., whose pumpkin weighed in at 2,501 pounds. This came close to the world record of 2,749 pounds, which was set earlier this year in California by fellow Minnesota grower Travis Gienger.

Though it was his largest, the Stillwater pumpkin wasn't Montsma's only giant pumpkin this year. He actually grew three.

One unfortunately broke and could not be used for competition, but the other pumpkin, at 1,782 pounds, earned Montsma third place at the Cedarburg Wine and Harvest Festival on Sept. 16 and 17.

Why did Tom Montsma start growing giant pumpkins?

A lifelong farmer, Montsma, who's 62, said he's been vegetable gardening since childhood. However, he only started growing giant pumpkins about a decade ago.

Montsma said he began his journey as a giant pumpkin grower in honor of his mom, who died of cancer a few years ago.

"Her and I one time were watching a TV story when she was going through her treatments," he recalled. "ABC had a story out east about big pumpkins, and I said, 'I could do that.' So, I made a promise to her that, someday, I would grow a 1,000-lb. pumpkin."

In 2017, Montsma saw that promise through.

"Then, five years later in 2022, I did my first 2,000-pounder, and I've just been really hooked," he continued. "It's a hobby now. Like other growers know, you just want to push the limit."

What species of pumpkin are giant pumpkins?

Most giant pumpkins used for competition are of the Atlantic Giant species. Growers can purchase Atlantic Giant seeds from regular seed catalogs, but most competitors also control the breeding and pollination of their plants to achieve maximum size.

"That's why the genetics are getting extremely, extremely strong," Montsma said.

The pumpkin-breeding process can be very involved. Female flowers are only open for four-to-six hours one morning.

"That's your only opportunity to breed or pollinate that pumpkin," Montsma explained. "If you miss that, then you have to wait another three, five, seven days until the next flower appears."

For his personal-record-breaking pumpkin this year, Montsma purchased seeds last year from the then-U.S. record holder in Minnesota.

"So, I knew that seed had potential, and, by George, it really did not let me down," Montsma said. "It averaged 50 pounds a day for 20 days straight."

How do you grow a giant pumpkin?

Growing a truly giant pumpkin isn't for the faint of heart.

"The average pumpkin grower will spend an hour a day from the middle of April until the middle of October when they harvest, pruning, trimming, fertilizing, watering, spraying and a lot of different other things," Montsma said.

He said he prunes the vines of his pumpkin plants all summer long, beginning in May, in order to divert as much of the plant's energy as possible into the fruit rather than the vine and leaves.

At the end of the day, growing the largest pumpkin possible comes down to what you're willing to put into it ― not monetarily, but timewise, Montsma said.

"Are you committed to pruning and sweating seven days a week? In June? In July?" he asked. "There are times when you're (caring for) your vines every night while everybody's on vacation or on the lake or at the golf course.

Of course, luck is also involved in giant pumpkin growing. Storms, flooding and other factors outside the grower's control can rot or break a pumpkin, disqualifying it from competition. Thankfully, this year, Montsma said the weather worked in his favor.

Because this summer was relatively dry, Montsma was able to control how much water his pumpkins received. He showered each one with about 100-to-150 gallons per day.

Usually, after all the effort that goes into growing pumpkins as large as Montsma's this year, some people suggest growers take a year off. However, Montsma said he plans to grow more next year and hopefully set another personal best.

"It's my competitive nature, and it's the fascination of learning so much more about what we can do to push these plants to see what the limit is," he said. "I've learned stuff every year."

Where can I see Tom Montsma's giant pumpkin?

Montsma's 2,360-pound pumpkin is currently on display in the parking lot at his son-in-law's business, Lake Country Health Center in Delafield, 1452 Genesee St.

Visitors are welcome to come take photos with it and the rest of the health center's fall display.

Once the pumpkin is off display, Montsma said he'll bring it home, harvest the seeds and put it in the back 40 of his family's farm property for wildlife to snack on.

This article originally appeared on Milwaukee Journal Sentinel: This Wisconsin farmer grows 2,000-pound giant pumpkins for fun