Ontario Plant Hardiness Zone Map
| Zone 0b -65°F to -60°F | Zone 1a -60°F to -55°F | Zone 1b -55°F to -50°F | Zone 2a -50°F to -45°F | Zone 2b -45°F to -40°F |
| Zone 3a -40°F to -35°F | Zone 3b -35°F to -30°F | Zone 4a -30°F to -25°F | Zone 4b -25°F to -20°F | Zone 5a -20°F to -15°F |
| Zone 5b -15°F to -10°F | Zone 6a -10°F to -5°F | Zone 6b -5°F to 0°F | Zone 7a 0°F to 5°F |
Based on the USDA Hardiness Zone Map Designations, this interactive version covers the Province of Ontario which ranges from USDA Zone 0b to USDA Zone 7a. What are Hardiness Zones, Gardening Zones, Growing Zones and Plant Zones? Hardiness Zones, Gardening Zones, Growing Zones and Plant Zones refer to defined geographic regions that can support specific plants, flowers and trees. T he zones define a minimum range of temperatures that a plant or tree can survive safely in that zone.
