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When to plant broccoli in zone 5b

In zone 5b, where the last spring frost typically comes around May 1, start broccoli indoors February 13 to March 6 and plant out April 3 to 17. For a fall crop, plant July 25 to August 22.

The zone 5b schedule for broccoli

Start seeds indoors
February 13 to March 6
Plant out
April 3 to 17
Sow outdoors
April 10 to 17
First harvest, roughly
May 23 to July 1
Plant for a fall crop
July 25 to August 22

From the median frost dates of the NOAA stations assigned to the 2,546 ZIP codes in zone 5b, and the timing recommended by Cooperative Extension guides for broccoli.

Dates before the last frost assume the soil has thawed and is dry enough to work: a squeezed handful crumbles instead of sticking. After a late or wet spring, wait for that even if the date has passed.

Frost risk in zone 5b

Zones are based on winter cold, not on frost dates, so the last spring frost varies a lot within a zone. Across zone 5b, the typical last frost ranges from about April 21 in the earliest tenth of ZIP codes to May 18 in the latest tenth, and the first fall frost from September 30 to October 19. For a typical place in the zone:

  • April 18Risky: a later frost happens in 9 years out of 10
  • May 1Typical: frost after this date in half of years
  • May 16Safe: a later frost only 1 year in 10

Your dates for broccoli

Set your ZIP code at the top of the page and we will work out when to plant broccoli where you live, from the frost records of the nearest NOAA weather station. Your ZIP code is remembered on this device only.

Enter your ZIP code

Broccoli in zone 5b cities

CityTypical last frostStart indoorsPlant out
Milwaukee, WIApr 19Feb 1 to 22Mar 22 to Apr 5
Madison, WIMay 1Feb 13 to Mar 6Apr 3 to 17
Des Moines, IAApr 18Jan 31 to Feb 21Mar 21 to Apr 4
Aurora, ILApr 19Feb 1 to 22Mar 22 to Apr 5
Fort Collins, COMay 2Feb 14 to Mar 7Apr 4 to 18
Naperville, ILApr 19Feb 1 to 22Mar 22 to Apr 5
Rockford, ILApr 24Feb 6 to 27Mar 27 to Apr 10
Elgin, ILApr 26Feb 8 to Mar 1Mar 29 to Apr 12
Greeley, COMay 2Feb 14 to Mar 7Apr 4 to 18
Green Bay, WIApr 30Feb 12 to Mar 5Apr 2 to 16
Davenport, IAApr 19Feb 1 to 22Mar 22 to Apr 5
Longmont, COMay 6Feb 18 to Mar 11Apr 8 to 22

How to grow broccoliAll zonesBroccoli in zone 5aBroccoli in zone 6aAbout zone 5b

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