FrostCal

When to Plant Radishes in Colorado

In a typical Colorado location, sow outdoors Mar 29 – Apr 12. Across the state, the outdoor planting window starts as early as Mar 10 in Grand Junction and as late as May 17 in Edwards. For a fall crop, plant around Aug 27 – Sep 10.

Method Direct sow
Days to maturity 22–30 days

Very fast and cold-hardy; direct sow 3-5 weeks before last frost, as soon as soil can be worked.

Radishes Planting Dates by City

CityDirect sowFall planting
DenverMar 26 – Apr 9Aug 31 – Sep 14
Colorado SpringsMar 29 – Apr 12Aug 27 – Sep 10
AuroraMar 30 – Apr 13Aug 27 – Sep 10
Fort CollinsMar 28 – Apr 11Aug 26 – Sep 9
LakewoodMar 29 – Apr 12Aug 26 – Sep 9
ThorntonMar 28 – Apr 11Aug 30 – Sep 13
WestminsterMar 28 – Apr 11Aug 30 – Sep 13
ArvadaMar 31 – Apr 14Aug 24 – Sep 7
CentennialMar 31 – Apr 14Aug 27 – Sep 10
PuebloMar 26 – Apr 9Aug 28 – Sep 11
GreeleyMar 28 – Apr 11Aug 27 – Sep 10
BoulderApr 1 – Apr 15Aug 24 – Sep 7
Highlands RanchMar 31 – Apr 14Aug 27 – Sep 10
LongmontApr 2 – Apr 16Aug 24 – Sep 7
LovelandApr 5 – Apr 19Aug 20 – Sep 3
BroomfieldMar 28 – Apr 11Aug 30 – Sep 13
Grand JunctionMar 10 – Mar 24Sep 11 – Sep 25
Castle RockApr 4 – Apr 18Aug 21 – Sep 4
Commerce CityMar 30 – Apr 13Aug 27 – Sep 10
ParkerApr 4 – Apr 18Aug 22 – Sep 5
LittletonMar 28 – Apr 11Aug 30 – Sep 13
NorthglennMar 28 – Apr 11Aug 30 – Sep 13
BrightonMar 29 – Apr 12Aug 26 – Sep 9
Dakota RidgeMar 28 – Apr 11Aug 30 – Sep 13
EnglewoodMar 28 – Apr 11Aug 30 – Sep 13
Security-WidefieldMar 29 – Apr 12Aug 27 – Sep 10
WindsorMar 29 – Apr 12Aug 25 – Sep 8
Ken CarylMar 28 – Apr 11Aug 30 – Sep 13
Wheat RidgeMar 31 – Apr 14Aug 24 – Sep 7
Pueblo WestMar 22 – Apr 5Sep 1 – Sep 15

Showing the 30 most populous of 65 Colorado cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Colorado cities.

Frequently Asked Questions

When should I plant radishes in Colorado?

In a typical Colorado location, sow outdoors Mar 29 – Apr 12. Across the state, the outdoor planting window starts as early as Mar 10 in Grand Junction and as late as May 17 in Edwards. For a fall crop, plant around Aug 27 – Sep 10.

When is the last frost in Colorado?

The average last spring frost in Colorado ranges from April 14 in Grand Junction to June 21 in Edwards, based on NOAA 1991–2020 climate normals.

How long do radishes take to grow?

Radishes typically take 22–30 days from planting to harvest. Very fast and cold-hardy; direct sow 3-5 weeks before last frost, as soon as soil can be worked.

Other Crops in Colorado

When to plant radishes in other states

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