Oh my gourd! Giant pumpkins in Lennoxville, QC

With fall officially here, it's time for Lennoxville, Quebec's annual Giant Pumpkin Festival, where people can see pumpkins that weigh as much as 680 kilograms.

The festival — which is taking place at the Amédée Beaudoin community centre Sunday from 11 a.m. to 4 p.m. — is a family event with bouncy castles, a petting zoo, a farmers' market, music and even horse-drawn carriages.

Alexandre Lemire started growing giant pumpkins three years ago after being inspired by festival founder Mike Macdonald's crops. Last year, his biggest pumpkin weighed 704 kilograms.

This year, he says he was disappointed he couldn't beat last year's performance because the weather conditions were poor, with a lot of rain, cooler temperatures and cloudy days. There were also more invasive insects than usual, he said. His other crops were also under strain this summer.

With climate change, challenging conditions for pumpkins may become more common, David Wees, Faculty Lecturer in McGill's Department of Plant Science and Associate Director of the Farm Management and Technology Program, told CBC News.

Though pumpkins need a lot of water to grow, too much of it can lead to diseases, like fungus, rot and mould. A common pumpkin disease is powdery mildew, a growth that Wees describes as "sprinkled powdered sugar on the leaves." And too much water in the soil can damage roots.

"A lot of wet weather in late summer, early fall can do a lot of damage to pumpkins and other vegetables."

But there are ways around the difficult weather, said Wees, such as temporary greenhouses, known as high tunnels, which keep plants warm and safe from excessive rain.

"We grow a lot of tomatoes here at MacDonald campus using the high tunnels and you can see the difference," he said. "The ones that are in the field, all the leaves have gone mouldy, whereas the ones in the high tunnels, the leaves are so much cleaner and drier and therefore a lot healthier."