As gardeners in a northern climate, we’re quite aware of the challenges of growing plants that may be borderline hardy in the region where we live. “Will it grow in my zone?” is the pertinent question about winter hardiness for perennial plants. Scientists have developed maps of plant hardiness zones for Canada based on seven climate variables (not only the average annual … [Read more...] about Plant hardiness zones changing, slowly
hardiness zones
Hardiness zones are drifting
The United States Department of Agriculture has updated its 1990 plant hardiness map, and it reveals that hardiness zones are drifting. The new USDA map reflects average cold temperatures from 1976 through 2005, and illustrates the warming trend we’ve noticed in recent winter seasons. The new data indicates an average 5°F temperature increase, making a half zone movement … [Read more...] about Hardiness zones are drifting