| 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 |
Based on the USDA Hardiness Zone Map Designations, this interactive version covers the Province of New Brunswick which ranges from USDA Zone 3a to USDA Zone 6b. 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.