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3a Planting calendar for zone 3a

USDA hardiness zone 3a: average annual extreme minimum -40°F to -35°F. 23 US ZIP codes fall in this zone.

Freeze dates for zone 3a

Median dates across 7 NOAA weather stations in zone 3a (1991–2020 normals). In zone 3a, the average coldest night of the year falls between -40°F and -35°F.

ThresholdLast spring freeze (median)Typical rangeFirst fall freeze (median)Typical range
32°F (freeze)May 25May 25 – May 25Sep 17Sep 17 – Sep 17
28°F (hard freeze)May 11May 11 – May 11Sep 27Sep 27 – Sep 27

Growing season at 32°F (50% probability): —.

Planting calendar — zone 3a

Cropjanfebmaraprmayjunjulaugsepoctnovdec
Tomatoes···SDT······
Peppers··SS·T······
Cucumbers····S
D
T······
Zucchini & Summer Squash····S
D
T······
Winter Squash & Pumpkins····S
D
T······
Snap Beans····D·F·····
Sweet Corn····D·······
Peas···D··F·····
Lettuce···S
D
STF·····
Spinach···D··F·····
Carrots···D··F·····
Radishes···D···F····
Broccoli···SS
D
TF·····
Garlic·······F····
Potatoes····D·······

S = start seeds indoors · T = transplant outside · D = direct sow · F = fall planting

Every crop, zone 3a