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Planting Zone 4b

Min winter temp -25 to -20ยฐF ยท last frost ~May ยท first frost ~September

Last spring frost
May 5
First fall frost
Sep 28
Growing season
146 days

In Zone 4b, the average last spring frost is around May and the first fall frost around September, about a 146-day growing season. Start tender crops indoors before the last frost and move them out once it passes.

Zone 4b planting calendar

Start indoors Transplant Direct sow Harvest
Crop JanFebMarAprMayJunJulAugSepOctNovDec
Tomatoes โ— โ— โ—
Peppers โ— โ— โ—
Cucumbers โ— โ— โ—
Lettuce โ— โ—
Zucchini โ— โ— โ—
Carrots โ— โ—
Beans (bush) โ— โ—
Peas โ— โ—
Broccoli โ— โ— โ—
Spinach โ— โ—
Kale โ— โ— โ—
Onions โ— โ— โ—
Garlic
Potatoes โ— โ—
Squash (winter) โ— โ— โ—
Corn โ— โ—
Radishes โ— โ—
Beets โ— โ—
Eggplant โ— โ— โ—
Basil โ— โ— โ—
Cilantro โ— โ—
Parsley โ— โ— โ—
Pumpkins โ— โ— โ—
Sunflowers โ— โ—

When to plant popular crops in Zone 4b

Frequently asked questions

When is the last frost in Zone 4b?

On average, the last spring frost in Zone 4b is around May; the first fall frost is around September.

What can I grow in Zone 4b?

Nearly all common vegetables and herbs grow in Zone 4b; the difference is timing. Use the planting calendar above, calculated from Zone 4b frost dates.

How long is the growing season in Zone 4b?

About 146 days between the average last spring and first fall frost.