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When to plant Coreopsis in Isabella County, MI

The best window to plant Coreopsis in Isabella County, is May 11–June 1, when soil warms to 50°F. Last frost typically hits May 4; first frost October 13.

When to Plant Coreopsis in Isabella County, MI

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.

Isabella County, Michigan is in USDA Zone 6a. The average last spring frost is May 4 and the first fall frost is October 13, giving you a growing season of approximately 162 days.

At an elevation of 1,136 feet, Isabella County receives approximately 35.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Coreopsis to ensure they mature before fall.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Isabella County, MI (Zone 6a) Moderate season
162 days
Last Spring Frost May 4
162 growing days
First Fall Frost October 13

Isabella County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Coreopsis Planting Timeline — Isabella County, MI

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors March 2 Mar 2 – Mar 16
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 11 May 11 – Jun 1
Bloom July 20 Jul 20 – Nov 9

Plant 0.1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April
May Transplant Outdoors Direct Sow
June Direct Sow
July Bloom
August Bloom
September Bloom
October Bloom
November Bloom
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

162 days in Isabella County

Growing Tips for Isabella County

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.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Coreopsis in Isabella County, MI?

Isabella County is in Zone 6a with an average last frost of May 4. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Isabella County, MI?

Isabella County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is May 4 and first fall frost is October 13.

When should I plant Coreopsis in Isabella County, MI?

In Isabella County, MI, plant Coreopsis after the last frost (around May 4) and before the first frost (around October 13). Best results when soil holds above 50°F.

What growing zone is Isabella County, MI for Coreopsis?

Isabella County sits in USDA Zone 6a. Coreopsis grows reliably in zones 3a through 9b, so it's a good fit here.

Can Coreopsis grow in Isabella County's climate?

Yes — Coreopsis grows well in Isabella County's temperate climate. Isabella County averages a 162-day frost-free season, with last frost around May 4 and first frost around October 13.

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Your Isabella County Garden Planner — Free

A 22-page printable planner built for Isabella County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Isabella County, MI. Local conditions may vary. Last updated: June 2026.

Sources & credits

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