FrostCal

When to Plant Marigolds in Colorado

In a typical Colorado location, start seeds indoors Mar 22 – Apr 5, then transplant outdoors May 10 – May 17. Across the state, the outdoor planting window starts as early as Apr 21 in Grand Junction and as late as Jun 28 in Edwards.

Method Start indoors, then transplant
Days to maturity 45–60 days

Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed.

Marigolds Planting Dates by City

CityStart indoorsTransplant
DenverMar 19 – Apr 2May 7 – May 14
Colorado SpringsMar 22 – Apr 5May 10 – May 17
AuroraMar 23 – Apr 6May 11 – May 18
Fort CollinsMar 21 – Apr 4May 9 – May 16
LakewoodMar 22 – Apr 5May 10 – May 17
ThorntonMar 21 – Apr 4May 9 – May 16
WestminsterMar 21 – Apr 4May 9 – May 16
ArvadaMar 24 – Apr 7May 12 – May 19
CentennialMar 24 – Apr 7May 12 – May 19
PuebloMar 19 – Apr 2May 7 – May 14
GreeleyMar 21 – Apr 4May 9 – May 16
BoulderMar 25 – Apr 8May 13 – May 20
Highlands RanchMar 24 – Apr 7May 12 – May 19
LongmontMar 26 – Apr 9May 14 – May 21
LovelandMar 29 – Apr 12May 17 – May 24
BroomfieldMar 21 – Apr 4May 9 – May 16
Grand JunctionMar 3 – Mar 17Apr 21 – Apr 28
Castle RockMar 28 – Apr 11May 16 – May 23
Commerce CityMar 23 – Apr 6May 11 – May 18
ParkerMar 28 – Apr 11May 16 – May 23
LittletonMar 21 – Apr 4May 9 – May 16
NorthglennMar 21 – Apr 4May 9 – May 16
BrightonMar 22 – Apr 5May 10 – May 17
Dakota RidgeMar 21 – Apr 4May 9 – May 16
EnglewoodMar 21 – Apr 4May 9 – May 16
Security-WidefieldMar 22 – Apr 5May 10 – May 17
WindsorMar 22 – Apr 5May 10 – May 17
Ken CarylMar 21 – Apr 4May 9 – May 16
Wheat RidgeMar 24 – Apr 7May 12 – May 19
Pueblo WestMar 15 – Mar 29May 3 – May 10

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 marigolds in Colorado?

In a typical Colorado location, start seeds indoors Mar 22 – Apr 5, then transplant outdoors May 10 – May 17. Across the state, the outdoor planting window starts as early as Apr 21 in Grand Junction and as late as Jun 28 in Edwards.

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 marigolds take to grow?

Marigolds typically take 45–60 days from planting to harvest. Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed.

Other Crops in Colorado

When to plant marigolds in other states

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