When to Plant Yarrow in Wisconsin

Achillea millefolium (Yarrow) is a tough, drought-tolerant native perennial with aromatic finely-divided foliage and broad flat-topped flower clusters that serve as a landing platform for hundreds of beneficial insect species. Available in white (the species type) and a wide range of cultivars spanning yellow, gold, pink, salmon, and deep red. Spreads by rhizome to form ground-covering colonies; blooms from late spring through midsummer with reblooming into fall if deadheaded. Exceptional in hot, dry sites where other perennials fail.

Wisconsin spans USDA hardiness zones 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 Yarrow planting dates based on your local frost dates.

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Yarrow Planting Calendar for Wisconsin

▸ 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	February 25	Feb 25 – Mar 11
Transplant Outdoors	May 20	May 20 – Jun 3
Direct Sow	May 6	May 6 – May 27
Bloom	August 5	Aug 5 – Oct 21

▸ 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	February 20	Feb 20 – Mar 6
Transplant Outdoors	May 15	May 15 – May 29
Direct Sow	May 1	May 1 – May 22
Bloom	July 31	Jul 31 – Oct 23

▸ 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	February 21	Feb 21 – Mar 7
Transplant Outdoors	May 9	May 9 – May 23
Direct Sow	April 25	Apr 25 – May 16
Bloom	July 18	Jul 18 – Oct 24

▸ 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	February 14	Feb 14 – Feb 28
Transplant Outdoors	May 2	May 2 – May 16
Direct Sow	April 18	Apr 18 – May 9
Bloom	July 11	Jul 11 – Oct 24

▸ 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 6	Feb 6 – Feb 20
Transplant Outdoors	April 17	Apr 17 – May 1
Direct Sow	April 10	Apr 10 – May 1
Bloom	June 26	Jun 26 – Oct 16

Growing Tips for Wisconsin

Start seeds indoors 8–10 weeks before last frost; seeds need light for germination — press onto soil surface, do not cover. Direct sow after last frost or divide established clumps in spring or fall. Thrives in poor, well-drained soil — rich soil and high fertility cause floppy stems and reduce flower count. Avoid overwatering; excellent drought tolerance once established. Deadhead spent clusters to encourage rebloom. Divide every 2–3 years to prevent center die-out and control spread. Year 2+ plants bloom most heavily; first-year plants may produce limited flowers. Dried flowers retain color well for arrangements.

Yarrow in Other States

Frequently Asked Questions

When should I plant Yarrow in Wisconsin?

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

What zone is Wisconsin for planting?

Wisconsin contains USDA hardiness zones 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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