When to Plant Coreopsis in Idaho

Coreopsis (Tickseed) is a cheerful, long-blooming native perennial that produces a continuous flush of bright yellow, gold, or bi-colored daisy-like flowers from early summer well into fall. One of the most reliable cut-and-come-again bloomers in the perennial garden, it thrives in hot, dry, sunny conditions and poor soil where many competitors struggle. An invaluable nectar source for native bees and butterflies, and a butterfly host plant for several species.

Idaho spans USDA hardiness zones 5a, 5b, 6a, 6b, 7a, 7b (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 Coreopsis planting dates based on your local frost dates.

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

Coreopsis Planting Calendar for Idaho

▸ 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	May 2	May 2 – May 23
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 25	Apr 25 – May 16
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 17	Apr 17 – May 8
Bloom	June 26	Jun 26 – Oct 16

▸ Zone 6b ~205 day growing season · Full guide →

Last frost: April 3 · First frost: October 25 · 205 day season

Activity	When	Date Range
Start Indoors	January 30	Jan 30 – Feb 13
Transplant Outdoors	April 10	Apr 10 – Apr 24
Direct Sow	April 3	Apr 3 – Apr 24
Bloom	June 19	Jun 19 – Oct 16

▸ Zone 7a ~221 day growing season · Full guide →

Last frost: March 25 · First frost: November 1 · 221 day season

Activity	When	Date Range
Start Indoors	January 21	Jan 21 – Feb 4
Transplant Outdoors	April 1	Apr 1 – Apr 15
Direct Sow	March 25	Mar 25 – Apr 15
Bloom	June 3	Jun 3 – Oct 14

▸ Zone 7b ~235 day growing season · Full guide →

Last frost: March 18 · First frost: November 8 · 235 day season

Activity	When	Date Range
Start Indoors	January 14	Jan 14 – Jan 28
Transplant Outdoors	March 25	Mar 25 – Apr 8
Direct Sow	March 18	Mar 18 – Apr 8
Bloom	May 27	May 27 – Oct 14

Growing Tips for Idaho

Start seeds indoors 8–10 weeks before last frost or direct sow after last frost. Seeds germinate easily without stratification. Thrives in poor to average, well-drained soil — rich soil promotes foliage over flowers. Drought tolerant once established; overwatering is the most common mistake. Deadhead spent blooms to maintain continuous flowering through the season. Shear plants by one-third in midsummer for a fresh flush of late-season blooms. Year 2+ plants bloom most heavily. Divide every 2–3 years in early spring to rejuvenate crowded clumps.

Coreopsis in Other States

Frequently Asked Questions

When should I plant Coreopsis in Idaho?

Planting dates for Coreopsis in Idaho depend on your USDA zone. Idaho spans zones 5a, 5b, 6a, 6b, 7a, 7b. Check the planting calendar above for your specific zone's frost dates and planting windows.

What zone is Idaho for planting?

Idaho contains USDA hardiness zones 5a, 5b, 6a, 6b, 7a, 7b. 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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