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When to Plant Sunchoke in Montana

Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.

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

Find Your County

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

Sunchoke 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
Transplant Outdoors May 24 May 24 – Jun 7
Harvest September 13 Sep 13 – 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
Transplant Outdoors May 20 May 20 – Jun 3
Harvest September 9 Sep 9 – Oct 14
Zone 4b ~155 day growing season · Full guide →

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

Activity When Date Range
Transplant Outdoors May 15 May 15 – May 29
Harvest September 4 Sep 4 – Oct 9
Zone 5a ~166 day growing season · Full guide →

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

Activity When Date Range
Transplant Outdoors May 9 May 9 – May 23
Harvest August 29 Aug 29 – Oct 24

Growing Tips for Montana

Plant tubers 4 inches deep in early spring. Contain plants with barriers as they spread aggressively. Harvest after frost or leave in ground and dig as needed through winter.

Frequently Asked Questions

When should I plant Sunchoke in Montana?

Planting dates for Sunchoke in Montana depend on your USDA zone. Montana spans zones 3b, 4a, 4b, 5a. 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. 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.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Last updated: April 2026.