Warmer summers could mean new plants growing in Manitoba, says horticulturalist

Manitoba's potential for longer and warmer growing seasons, coupled with wild weather changes, could change how people approach gardening in the province, experts say.

While it's hard to predict whether the province will start to see alonger or earlier growing season,plant types and growing patterns are changing in tandem with the climate, says Sajjad Rao,ahorticulture research instructor at Brandon'sAssiniboine Community College.

"We're shifting," he said, and the time to start adapting is now.

"The changes coming from the climate is compelling us to do that, because then we have to come to a resilient agriculture, or a resilient horticulture."

Most of southern Manitoba is designated a cold-climate Zone 3 plant hardiness zone but there are spots whereZone 4 plants, which thrive in warmer environments, can now be grown,Rao said.

Globally, last summerwas one of the hotteston record.This past December, January and February were the warmest on record in Canada in 2024.

Manitoba has also seen swings from drought toflooding in recent years.In 2022, several climate experts told CBC that may be a sign of things to come and a reminder that people need to be prepared for more extreme weather in the future.

In Brandon, gardeners are trying to adapt to these changes in weather and climate.

While spring planting typically still startsaround the May long weekend, gardeners are changing how they maintain plants in the summer. Thatincludes steps like increasing mulch usage,saidBrian Fowell, a co-ordinator with Brandon's Hummingbird Community Garden.

"During the summer we do get hotter, which make[s] such a difference with our water we have here," he said.

"Butif you water, put some mulch down, you can keep that water because if not, everything wilts out in the heat."

Other changes include trying to grow new types of vegetables, along with long-time staples like carrots and squashes, he said.

Gradual gardening changes

Changes to Manitoba's climate are gradual, but they start to add up, Rao said.

He cited frost-free days in Brandon as an example typically, the area gets about 105, and at mostabout 117 in a year. Butby 2050, that number is expected to grow by at least 30 days, based on data and research, Rao said.

That means there will be a longer and warmer growing season, which could lead to planting different crops, Rao said.

Some planting changes are already starting to happen, with some tropical plants like sweet potatoes and okra, which prefer the heat, being introduced to Manitoba as the climate warms, Rao said.

The Green Spot owner Bernie Whetter says his Brandon greenhouse hasn't seen drastic changes in the plants people want butZone 4 plants are starting to pop up.

Brandon is designated Zone 3, whichgenerally requires "pretty hardy stock" when it comes to perennials or nursery stock, Whetter said.

However, growers are finding some Zone 4 plants may be ablefit into the Manitoba climate, because there has been incremental warmingeach year, he said.

"We are able to stretch those zones a little bit," said Whetter. "It's always changing. It's a slow but gradual change."

Growing gardens

Melanie Hellyer, a co-ordinator with Hummingbird Community Garden, says the gardengrowing season there hasn't had a real changesince the community gardenstarted in 2007.

They typically hold off on planting until the May long weekend to prevent frost damage and harvest everything by the start of October.

Rao cautions nothing can be predicted with total certainty when it comes to weather and climate. That means gardeners, farmers and horticulturalists need to start makingdecisions and strategically planning to manage the impacts of climate change on their plants.

Technology is also changing with the climate, he said.Breeders and plant scientists are working with technology, including artificial intelligence, to gatheras much information as possible to understand the impacts of climate change, Rao said.

"We can get some real sense that it is shifting. heat waves are unpredictable, droughts and floods are very unpredictable," Rao said.

"We need to move in a way so we can face those challenges in a better way and ... have a solution for them."