As climate change warms the planet and growing regions shift further north, more fruits and vegetables – even citrus fruits – could start making the journey to the United States from Canada. Extreme winter cold and shorter growing seasons historically have prevented certain crops from being grown there, but as temperatures rise and first frosts happen later, the time could be ripe for Canadian farmers to expand their ranges.

“We’re seeing that here in Canada, particularly in Southern Ontario, people are pushing the limits,” John Pedlar, a Canadian Forest Service biologist, said. Pedlar helped author a study last year that found that a shift in growing regions may be more closely tied to climate change than previously thought.

“We’re starting to see a lot more grapes grown up here,” said Pedlar, whose work was published in the journal BioScience. “People are trying their hand at things like peaches a little further north from where they have been trying. Presumably, that kind of thing is just going to increase.”

The lowest temperature lows have helped U.S. farmers and gardeners determine what species they can plant – and when they can plant them – for decades. The United States Department of Agriculture (USDA) released its first Plant Hardiness Zone Map (PHZM) in the early 1960s, and over the years, the map’s recommended zones have been based on the average extreme minimum temperatures over a prescribed number of years.

Nir Krakauer, a City College of New York professor, believes the USDA’s findings may be more tied to climate change than the researchers originally thought.

Source - http://www.freshplaza.com/