Planting before the May long weekend? It depends what you want to grow, and how

As sure as spring frost turns to morning dew, gardeners are once again weighing the old maxim that you shouldn't plant before the May long weekend if you want to reap a healthy harvest.

Should you wait for June's first moon? Or does a changing climate mean an earlier final frost?

More than a dozen early spring shoppers were browsing the hollyhocks, roses and compost at the east-end location of Ritchie Feed and Seed when CBC News visited on a recent weekday morning to ask about their long weekend plans. 

"That has changed. It's now the middle of May," said Sheila Lang, who was looking for climbing roses. "I guess it's global warming or whatever."

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Stephanie Dragan was looking for Canadian-bred roses, all the better to take advantage of the sunny weather.

"Just because the weather seems to be warming up and so I find we can get a little bit more of a head start on the season," she said. "Things like cold weather vegetables, roses — I like to get planted out a little bit early."

Benoît Côté prefers observable measurement over groundhogs, almanacs or old sayings.

"You subscribe to what the weather is and what good old Environment Canada and other people are telling you," he advised. "You just go with it."

On top of the warmer weather, Victoria Day falls relatively early this year on May 19.

The garden centre's general manager warned you never know when a late frost will strike.

"That wisdom is mainly for annuals and veggies and stuff that are a little less frost-hardy. Usually in May, as long as the soil is warmed up enough, perennials, trees, shrubs — they can go in earlier," Michael Ritchie said.

Protect your 'babies'

At the Growing Together Community Farm near Shirley's Bay in Ottawa's west end, volunteers start their first shifts in the second week of May, and there's a greenhouse prepped for a seedling sale on the weekend of May 24. 

Maureen Russell, a self-described "crazy tomato lady," is organizing this year's sale and understands the temptation people feel when they bring home a fresh bounty.

"They're so eager to put them out in the garden, and that's when you're going to get failure," she said. 

Russell uses improvised cloches made by cutting the bottoms off plastic bottles to get her tomato plants going. She has also draped sheets and towels over plants to shield them from a late May frost.

"I'm an anxious gardener," she said. "You can take chances with your seeds, but you also need to protect them because they're babies!"

Plant and harvest all year

Over in the Aylmer sector of Gatineau, Hélène Hébert is already harvesting spinach, onions and other hardy crops under the protection of a low fabric tunnel.

"Most gardeners in Canada are just begging for the last frost day to happen, and I don't care about that! I really don't. I just plant whatever is adapted for the season I'm in," she said.

Hébert is a gardening coach with online courses on year-round gardening. 

She said climate change has made summertime gardens more vulnerable to hazards such as hail in the spring. She said without protection for heat-loving plants like tomatoes and peppers, gardeners may want to wait until the second weekend of June to plant outside.

Meanwhile, Hébert said her shoulder seasons are benefiting from warmer winters. Spinach she planted in October is ready for harvest, and she added spring plants in March.

"Where I planted my spring garden used to be my winter garden…. The soil in there thawed while there was still snow around, so I was able to start planting my spring garden early," she said.

"It gives you so much more freedom. It shatters the limitations we think we're bound to [in] gardening."