Subarctic

What Can Grow in Zone 1b

Subarctic zone with minimal growing season. Container gardening and cold frames essential for most crops.

Zone 1b has average winter lows of -55°F to -50°F (-48°C to -46°C). You can grow kale, cabbage, radishes, and many more plants. The frost-free growing season lasts about 55 days.

-55°FWinter Low
-50°FWinter High
55 daysFrost-Free
June 10Last Frost
August 20First Frost
🥕 Vegetables
kale cabbage radishes turnips lettuce spinach peas mustard greens
🍎 Fruits
cloudberries crowberries lingonberries gooseberries
🌿 Herbs
chives mint dill parsley
🌸 Flowers
pansies snapdragons marigolds arctic poppies
🌳 Trees & Shrubs
tamarack white spruce paper birch trembling aspen
💡 Planting Tips

Use raised beds with dark-colored soil to absorb heat. Cold frames extend season by 4-6 weeks. Choose varieties with shortest days-to-maturity.

🌱
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📍 States in Zone 1b
Alaska
🔀 Neighboring Zones
1a2a

Frequently Asked Questions

USDA Zone 1b has average annual minimum temperatures of -55°F to -50°F (-48°C to -46°C). This temperature range determines which perennial plants can survive winter outdoors.

The average last frost date in Zone 1b is around June 10, and the first fall frost typically arrives around August 20. This gives a frost-free growing season of approximately 55 days.

Zone 1b is well-suited for kale, cabbage, radishes, turnips, lettuce, spinach. Use raised beds with dark-colored soil to absorb heat. Cold frames extend season by 4-6 weeks. Choose varieties with shortest days-to-maturity.

Fruits that thrive in Zone 1b include cloudberries, crowberries, lingonberries, gooseberries. Always check that specific cultivars are hardy to your zone before planting perennial fruit trees and shrubs.