Earlier, we talked about animals migrating up mountains to find cooler temperatures, in response to a warming climate. Well, crops are migrating, too.

The USDA map of plant hardiness divides North America into 13 zones.

Zone 1 is farthest north, with winters colder than 50 below zero. Zone 13 is farthest south, with winters around 60 degrees Fahrenheit.

Over the last 30 years, all zones have shifted a half zone to the north, as average winter temperatures increased across the Lower 48.

Models predict that plant zones will continue to move north, about 13 miles a year. And it’s happening all over the world. In Australia, the wheat belt is moving 16 miles a year.

In response, farmers in many countries have had to change the times of year they plant or harvest. Some now have a second growing season.

Warmer weather and longer seasons have allowed some farmers to grow more lucrative crops, in higher quantities—while others have seen traditional crops fail and prized land lose its value.

Where might they go for new opportunities?

As northern latitudes get warmer, lands that were once too cold to farm may become plantable. In fact, Canada is preparing for millions of acres in its northern prairies to replace farmland potentially lost in the south.

The warming climate will continue to change plant distribution and farming practices—with both positive and negative effects on global agriculture and food supply.