When Is the Last Frost?

Zone 4b planting calendar

USDA zone 4b has average winter lows of -25°F to -20°F. Across 1,284 ZIP codes in this zone, the typical last spring frost is May 8 and the first fall frost is October 1.

Zone dates are an average — get your own

Zone 4b vegetable planting calendar

Crop
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Start indoors: Feb 13 to Feb 27Transplant outside: Apr 10 to Apr 24
Start indoors: Feb 27 to Mar 13Transplant outside: May 22 to Jun 5
Start indoors: Feb 27 to Mar 13Transplant outside: May 22 to Jun 5
Start indoors: Mar 13 to Mar 27Transplant outside: May 15 to May 29
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 17 to May 1Sow outdoors: Apr 10 to May 15Plant for fall: Aug 6 to Sep 3
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 10 to Apr 24Sow outdoors: Apr 10 to Apr 24Plant for fall: Jul 23 to Aug 13
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 24 to May 8Plant for fall: Jun 25 to Jul 16
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 17 to May 1Plant for fall: Jun 25 to Jul 16
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 24 to May 8Plant for fall: Jun 25 to Jul 16
Start indoors: Mar 27 to Apr 10Transplant outside: May 29 to Jun 12Sow outdoors: May 29 to Jun 12
Start indoors: Mar 27 to Apr 10Transplant outside: May 15 to May 29
Sow outdoors: Mar 27 to Apr 17Plant for fall: Jul 9 to Jul 30
Sow outdoors: Mar 27 to Apr 17Plant for fall: Aug 6 to Aug 27
Sow outdoors: Apr 3 to May 15Plant for fall: Aug 20 to Sep 10
Start indoors: Apr 10 to Apr 17Transplant outside: May 22 to May 29Sow outdoors: May 15 to May 29Plant for fall: Jul 16 to Jul 30
Start indoors: Apr 10 to Apr 17Sow outdoors: May 15 to May 29Plant for fall: Jul 23 to Aug 6
Start indoors: Apr 10 to Apr 17Sow outdoors: May 15 to May 29
Start indoors: Apr 10 to Apr 17Transplant outside: May 22 to Jun 5
Sow outdoors: Apr 17 to May 15Plant for fall: Jul 9 to Jul 23
Sow outdoors: Apr 17 to May 15Plant for fall: Jul 23 to Aug 6
Sow outdoors: Apr 17 to May 8
Sow outdoors: Apr 24 to May 22Plant for fall: Jul 23 to Aug 6
Sow outdoors: Apr 24 to May 15Plant for fall: Aug 6 to Aug 27
Sow outdoors: May 15 to Jun 5Plant for fall: Jul 16 to Jul 30
Sow outdoors: May 15 to May 29
Transplant outside: May 22 to Jun 12
Plant for fall: Sep 17 to Oct 22
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates

When to plant in zone 4b

CropStart indoorsTransplantSow outdoorsFall crop
OnionsFeb 13 – Feb 27Apr 10 – Apr 24——
PeppersFeb 27 – Mar 13May 22 – Jun 5——
EggplantFeb 27 – Mar 13May 22 – Jun 5——
TomatoesMar 13 – Mar 27May 15 – May 29——
LettuceMar 13 – Mar 27Apr 17 – May 1Apr 10 – May 15Aug 6 – Sep 3
KaleMar 13 – Mar 27Apr 10 – Apr 24Apr 10 – Apr 24Jul 23 – Aug 13
BroccoliMar 13 – Mar 27Apr 24 – May 8—Jun 25 – Jul 16
CabbageMar 13 – Mar 27Apr 17 – May 1—Jun 25 – Jul 16
CauliflowerMar 13 – Mar 27Apr 24 – May 8—Jun 25 – Jul 16
OkraMar 27 – Apr 10May 29 – Jun 12May 29 – Jun 12—
BasilMar 27 – Apr 10May 15 – May 29——
Peas——Mar 27 – Apr 17Jul 9 – Jul 30
Spinach——Mar 27 – Apr 17Aug 6 – Aug 27
Radishes——Apr 3 – May 15Aug 20 – Sep 10
CucumbersApr 10 – Apr 17May 22 – May 29May 15 – May 29Jul 16 – Jul 30
Zucchini & Summer SquashApr 10 – Apr 17—May 15 – May 29Jul 23 – Aug 6
Winter Squash & PumpkinsApr 10 – Apr 17—May 15 – May 29—
Melons & WatermelonApr 10 – Apr 17May 22 – Jun 5——
Carrots——Apr 17 – May 15Jul 9 – Jul 23
Beets——Apr 17 – May 15Jul 23 – Aug 6
Potatoes——Apr 17 – May 8—
Swiss Chard——Apr 24 – May 22Jul 23 – Aug 6
Cilantro——Apr 24 – May 15Aug 6 – Aug 27
Green Beans——May 15 – Jun 5Jul 16 – Jul 30
Sweet Corn——May 15 – May 29—
Sweet Potatoes—May 22 – Jun 12——
Garlic———Sep 17 – Oct 22