It took fertilizer, the greenest of thumbs and a pair of pantyhose for Dan MacCoy to grow his record-breaking tomato, a lobed behemoth that looked something like a partially-inflated beach ball when he finally plucked it.

The deli scale at the grocery store in Ely, Minn., confirmed the tomato's monster status: 8.41 pounds, enough that MacCoy expects the Guinness World Records to eventually certify it as the heaviest tomato ever grown.

"It was pretty amazing to see that number come up," MacCoy said Monday. The weigh-in at Ely's Northland Market prompted "jumping and cheering" among people in the grocery store that day, he said.

The weigh-in was witnessed by a representative of the Great Pumpkin Commonwealth, the non-profit organization that oversees the hobby of world-record fruit growing.

If no one else comes up with a heavier tomato by Nov. 1, MacCoy can lay claim to the tomato title. He doesn't expect anyone to beat him, though. The previous record has stood for 28 years, ever since painting contractor Gordon Graham of Edmond, Okla., discovered a single, mammoth tomato growing on a vine that had been toppled by a storm. He nursed it along until it weighed 7.75 pounds, the record since 1986. The tomato was considered so large that for several years after Graham's story made national news, fertilizer company Miracle-Gro offered a $100,000 prize to anyone who could better it.

MacCoy originally didn't intend to grow big tomatoes, he said. A few years ago, he started out in his 300 sq. ft. greenhouse with an attempt at a record-breaking pumpkin. It wasn't to be. His best pumpkin weighed 1,197 pounds, well shy of the state record 1,779 pounds.

Dan MacCoy with his 8.41 pound tomato.

"I thought to myself, 'I'm never going to come close to a world record,'" said MacCoy, who with his wife Sara and daughter, Aspen, 2, tends a variety of vegetable gardens inside their greenhouse.

Using the same network of growers he met online while vying for a record pumpkin, he found a grower in France who had "Big Zac" tomato seeds to share. MacCoy grew four plants last year and ended up with a 4.57 pound tomato. He used the seeds from that tomato to grow 10 plants this year.

The Big Zac variety tends to have "megablooms," with individual tomatoes growing fused together. MacCoy said his record-breaking tomato looks like five individual fruits wrapped into one.

He started the plants on April 15 indoors, then moved them to his greenhouse in early May. From there he carefully pruned the plants of all other growth except the vine supporting his tomato, using a theory that a small plant would produce larger tomatoes.

Dehydrated chicken manure, kelp meal, humic acid, triple-10 fertilizer and other "stuff like that" kept the soil nourished, said MacCoy. Even the watering was by design: he watered the plant by hand using rainwater he collected in a barrel. When the tomato's weight became too much for the plant, Sara bought a pair of pantyhose to use as a sling to support it.

He kept a diary of the growing season at the website Bigpumpkins.com, a forum for growers of big gourds.

Measuring the tomato as it grew he estimated its weight at more than eight pounds in late August, but when he picked it Aug. 29, he still wasn't sure. The tomato was 47 days old at that point and he guessed it was at its peak weight. Then came the trip to the grocery store located across the street from his employer, Hearthside Corner, where he sells and installs fireplaces.

So what became of it?

MacCoy carefully extracted all of its seeds and plans to give them away to other competitive growers or auction them off to support the Great Pumpkin Commonwealth to help pay for the weigh-off events it holds every year around the country. The seeds could be worth about $16,000, he said, but much of the rest of the tomato ended up in his compost pile.

Some of the seeds, known officially as "8.41 MacCoy Big Zac," will go to competitive growers in France and the United Kingdom, he said.

"It's crazy," he said, speaking of other growers hoping to find a monster tomato lurking in their garden. "It's going to help a lot of people out."

Matt McKinney • 612-673-7329