When to Plant Marigolds in Montana

Marigolds (Tagetes patula) are warm-season annuals beloved for their cheerful orange, yellow, and red blooms — and for their well-documented ability to repel pest nematodes in vegetable beds. Easy from seed, drought-tolerant once established, and bloom from early summer until the first hard frost.

Montana spans USDA hardiness zones 3b, 4a, 4b, 5a, 5b, 6a (with planting data available), so planting dates vary by your location within the state. Click your zone below for the most accurate dates.

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Click your county for exact Marigolds planting dates based on your local frost dates.

Hover over a county to see details. Click to view planting guide.

Marigolds Planting Calendar for Montana

▸ Zone 3b ~135 day growing season · Full guide →

Last frost: May 10 · First frost: September 22 · 135 day season

Activity	When	Date Range
Start Indoors	March 29	Mar 29 – Apr 12
Transplant Outdoors	May 24	May 24 – Jun 7
Direct Sow	May 24	May 24 – Jun 14
Bloom	July 19	Jul 19 – Sep 27

▸ Zone 4a ~145 day growing season · Full guide →

Last frost: May 6 · First frost: September 28 · 145 day season

Activity	When	Date Range
Start Indoors	March 25	Mar 25 – Apr 8
Transplant Outdoors	May 20	May 20 – Jun 3
Direct Sow	May 20	May 20 – Jun 10
Bloom	July 15	Jul 15 – Sep 30

▸ Zone 4b ~155 day growing season · Full guide →

Last frost: May 1 · First frost: October 3 · 155 day season

Activity	When	Date Range
Start Indoors	March 20	Mar 20 – Apr 3
Transplant Outdoors	May 8	May 8 – May 22
Direct Sow	May 8	May 8 – May 29
Bloom	July 3	Jul 3 – Sep 18

▸ Zone 5a ~166 day growing season · Full guide →

Last frost: April 25 · First frost: October 8 · 166 day season

Activity	When	Date Range
Start Indoors	March 14	Mar 14 – Mar 28
Transplant Outdoors	May 2	May 2 – May 16
Direct Sow	May 2	May 2 – May 23
Bloom	June 27	Jun 27 – Sep 19

▸ Zone 5b ~178 day growing season · Full guide →

Last frost: April 18 · First frost: October 13 · 178 day season

Activity	When	Date Range
Start Indoors	March 7	Mar 7 – Mar 21
Transplant Outdoors	April 25	Apr 25 – May 9
Direct Sow	April 25	Apr 25 – May 16
Bloom	June 20	Jun 20 – Sep 19

▸ Zone 6a ~193 day growing season · Full guide →

Last frost: April 10 · First frost: October 20 · 193 day season

Activity	When	Date Range
Start Indoors	February 27	Feb 27 – Mar 13
Transplant Outdoors	April 17	Apr 17 – May 1
Direct Sow	April 17	Apr 17 – May 8
Bloom	June 12	Jun 12 – Sep 11

Growing Tips for Montana

Direct-sow after last frost or start indoors 4-6 weeks earlier. Deadhead spent blooms to keep new flowers coming. French marigolds (T. patula) are the most reliable nematode repellents — plant a band around vegetable beds. Tolerate poor soil but bloom best with monthly compost.

Marigolds in Other States

Frequently Asked Questions

When should I plant Marigolds in Montana?

Planting dates for Marigolds in Montana depend on your USDA zone. Montana spans zones 3b, 4a, 4b, 5a, 5b, 6a. Check the planting calendar above for your specific zone's frost dates and planting windows.

What zone is Montana for planting?

Montana contains USDA hardiness zones 3b, 4a, 4b, 5a, 5b, 6a. Your specific zone depends on your location within the state — northern and higher-elevation areas are in colder zones, while southern and coastal areas are warmer.

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