USDA Hardiness Zones

Find Your USDA Hardiness Zone

Knowing your growing zone helps determine which plants will thrive in your climate.

Zone Map

The USDA Plant Hardiness Zone Map is the standard by which gardeners can determine which plants are most likely to thrive in their location. The map is based on the average annual minimum winter temperature, divided into 13 zones.

Understanding USDA Hardiness Zones

USDA Hardiness Zones divide North America into regions based on average annual minimum winter temperatures. Each zone represents a 10°F difference, with subzones (a/b) representing 5°F increments. This system helps gardeners determine which plants are likely to survive in their climate.

Zone Descriptions

Zone 2: -50°F to -40°F

Very short growing season (90-100 days), extremely cold winters

Zone 3: -40°F to -30°F

Short growing season (120-150 days), very cold winters

Zone 4: -30°F to -20°F

Cold winters, spring frosts possible until late May

Zone 5: -20°F to -10°F

Cold winters, moderate growing season (150-175 days)

Zone 6: -10°F to 0°F

Moderate growing season (175-200 days), cold winters

Zone 7: 0°F to 10°F

Long growing season (200+ days), mild winters

Zone 8: 10°F to 20°F

Long growing season, mild winters, hot summers

Zone 9: 20°F to 30°F

Very long growing season, mild winters, hot summers

Zone 10: 30°F to 40°F

Nearly year-round growing, very mild winters

Zone 11: Above 40°F

Year-round growing, frost-free tropical climate

General Planting Guidelines by Zone

Cold Zones (2-4)

Start cool-season crops indoors 6-8 weeks before last frost
Focus on cold-hardy vegetables: kale, spinach, carrots, potatoes
Use season extenders like cold frames and row covers
Choose short-season varieties (70 days or less to maturity)
Plant perennials rated for at least one zone colder than yours

Moderate Zones (5-7)

Good balance of cool and warm-season crops
Start warm-season crops after soil temperatures reach 60°F
Use succession planting for continuous harvests
Fall garden opportunities with second plantings of cool-season crops
Great for most perennial fruits and ornamentals

Warm Zones (8-10)

Focus on heat-tolerant varieties during summer
May need shade cloth for cool-season crops
Consider two main growing seasons: spring and fall
Some warm regions have summer gardening breaks due to extreme heat
Winter growing season for cool-season crops

Frost Date Considerations

Your frost dates are crucial for successful gardening, even more specific than your zone:

Spring Planning:

Last spring frost marks when it's safe to plant tender crops outdoors
Start seeds indoors 4-8 weeks before last frost date
Harden off seedlings by gradually introducing them to outdoor conditions

Fall Planning:

First fall frost date signals the end of the growing season for tender plants
Calculate planting dates for fall crops by counting back from first frost date
Use row covers to extend your season beyond first light frosts

Microclimate Factors

Your garden may have conditions that differ from the overall zone:

Urban Heat Islands

City environments may be 5-10°F warmer than surrounding areas

Water Proximity

Lakes, rivers, and oceans moderate temperatures

Elevation

Higher elevations experience colder temperatures

Slope Direction

South-facing slopes are warmer than north-facing slopes

Wind Exposure

Wind can significantly lower effective temperatures

Structures

Buildings, walls, and hardscaping can create warmer microclimates

Seasonal Adaptations

Cold Zones (2-4):

Focus on rapid spring soil warming with raised beds
Use season extenders: cold frames, row covers, greenhouses
Select fast-maturing varieties

Moderate Zones (5-7):

Balance cool and warm-season crops
Plant cool-season crops in early spring and fall
Plant warm-season crops after soil warms

Warm Zones (8-10):

Consider summer dormancy for some plants
Focus on heat-tolerant varieties
Plant cool-season crops in fall through spring