After being a society member for more than 30 years, Mr Grant (89) achieved a personal first by winning the "Champion of Champions" award at the society’s annual show on Saturday, with his yellow, Netherlands-bred rose Glorious.
"It’s taken me 30 years to do this," he said.
"A good rose is a beautiful thing," he added.
"They fill up the space and make the place look good."
Mr Grant, of Dunedin, said a good supply of patience and a sense of humour came in handy in growing roses.
Ultimately, nature was beyond human control, and heavy winds and rain could badly damage or destroy promising blooms despite a great deal of effort in growing them, he said.
He had been growing roses for more 30 years and, having initially been a vegetable gardener, he had been inspired to turn his hand to roses by his late wife, Catherine.
"People ask me, ‘What’s your favourite rose?’ and I always say ‘The one that’s out in flower at the moment’.
"You’ve got to have a laugh about these things, specially when the wind blows and rain falls on the blooms."
He was still keen on growing tomatoes too.
Society president Linda Hellyer said that simply holding the annual show on time had been a "victory", given that last month had been the wettest Dunedin November on record, and had more rain since.
"We were pleased to see the sunshine this week."
Some flowers at the Forbury Park Raceway show had been blemished by the bad weather, but the number of entries was similar to last year, and they were also of good quality, she said.
"It surprised us with the weather that we had such good entries as well."
Organisers had been "worried about" last month’s wet weather, but "cancellation would have to be an absolutely very, very last resort," she said.
