Hardiness Zones: USDA Map for Outdoor Plant Survival

USDA Hardiness Zones: Minimum Winter Temperatures Define Zones

Hardiness zones are geographic areas defined by minimum winter temperatures. Zone 10 = 30–40°F (-1 to 4°C). Helps choose outdoor plants, but ignores summer heat—same zone can have vastly different summers. For indoor plants, toxicity levels matter more: Level 1 (mild irritation), Level 2 (vomiting, diarrhea), Level 3 (severe symptoms), Level 4 (life-threatening). Check toxicity before buying; call Poison Control (1-800-222-1222) if ingestion occurs.