He's nearing six months retired after selling his Youngtown facility in December, but you'd be wrong to think he's not keeping busy.

The 86-year-old spent Wednesday morning harvesting a bumper crop of pumpkins he'd grown in his front yard in Norwood.

His son-in-law Patrick then helped load more than half a tonne of sweet greys into a ute and couriered them direct to Launceston's Salvation Army kitchen.

"I think they might give some of them away to people that are needy, and I guess they make a lot of soup for underprivileged people that come there for a meal," Mr Allan said.

"If you leave the stalk on them and turn them every now and then [they'll last] for another six or seven months.

"Especially that variety - it's a nice sweet pumpkin, but it's a very good keeper."

The crop included plenty of specimens topping the 10kg mark.

Mr Allan humbly hosed down suggestions they were the best pumpkins in Tasmania, but happily shared some tricks of the trade.

"There's no science to growing them - they love water in their growing period," he said.

"One of the best secrets is once they get two or three pumpkins on the vine to nip the end off the runner so all the growth goes back into the pumpkin."

The crop was grown on a quarter-acre block adjoining Mr Allan's home, which he believes is one of the biggest plots in Norwood.

He bought the land off former Deputy Prime Minister Lance Barnard, who served Bass for 21 years between 1954 and 1975.

A sign - 'Allan's flower and vegetable plant specialists' - hangs off a greenhouse in the corner of the property, and he is also growing chillies, eggplants, strawberries and watermelons.

He said watermelons were not difficult to grow in Tasmania, contrary to popular belief.

"We grew them last year and I had about 20 as big as basketball but I was a bit late putting them in this year," he said.

"A lot of people think they are [hard to grow] but they're not really if you get a nice warm spot, plenty of water."

The site is a far cry from the bustle of his iconic Youngtown nursery, but still very much a gardener's paradise.

"I miss it because I've done nothing else for 59 years - naturally I miss it," he said.

"But I'm not bored because I've got this little [patch] to keep me quiet."