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When to Plant Rhubarb in Iowa

Rhubarb is a long-lived perennial vegetable grown for its tart, colorful stalks. Only the stalks are edible as the leaves contain toxic oxalic acid.

Iowa spans USDA hardiness zones 4b, 5a, 5b (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 Rhubarb planting dates based on your local frost dates.

Rhubarb Planting Calendar for Iowa

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 29 May 29 – Jun 12
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 16 May 16 – May 30
Zone 5b ~178 day growing season · Full guide →

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

Activity When Date Range
Transplant Outdoors May 9 May 9 – May 23

Growing Tips for Iowa

Plant crowns in early spring in rich, well-drained soil. Do not harvest stalks the first year. Pull (do not cut) stalks at harvest to avoid introducing rot.

Frequently Asked Questions

When should I plant Rhubarb in Iowa?

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

What zone is Iowa for planting?

Iowa contains USDA hardiness zones 4b, 5a, 5b. 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.