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3b Planting calendar for zone 3b

USDA hardiness zone 3b: average annual extreme minimum -35°F to -30°F. 230 US ZIP codes fall in this zone.

Freeze dates for zone 3b

Median dates across 110 NOAA weather stations in zone 3b (1991–2020 normals). In zone 3b, the average coldest night of the year falls between -35°F and -30°F.

ThresholdLast spring freeze (median)Typical rangeFirst fall freeze (median)Typical range
36°F (light freeze — tender plants hurt)May 29May 25 – Jun 1Sep 12Sep 8 – Sep 17
32°F (freeze)May 19May 14 – May 26Sep 21Sep 16 – Sep 26
28°F (hard freeze)May 8May 3 – May 18Sep 29Sep 23 – Oct 4

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

Planting calendar — zone 3b

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

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

Every crop, zone 3b