When to plant Coreopsis in Cass County, MI
Cass County gardeners should plant Coreopsis between May 6 and May 27 in spring. With Cass County's Zone 6a climate (last frost April 29), Coreopsis needs 60–80 days to mature — plant by July 29 for a full harvest.
When to Plant Coreopsis in Cass 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.
Cass County, Michigan is in USDA Zone 6a. The average last spring frost is April 29 and the first fall frost is October 17, giving you a growing season of approximately 171 days.
At an elevation of 1,030 feet, Cass County receives approximately 34.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Coreopsis during the growing season.
Cass County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.2
Drainage
Well Drained
Monthly Watering Guide for Coreopsis
Coreopsis needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Coreopsis Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| May | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Jun | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Aug | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Sep | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Oct | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Nov | — | 2.1" | 0" | ❄️ Dormant |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Cass County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Coreopsis Planting Timeline — Cass County, MI
Coreopsis Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 25 | Feb 25 – Mar 11 |
| Transplant Outdoors | May 6 | May 6 – May 20 |
| Direct Sow | May 6 | May 6 – May 27 |
| Bloom | July 15 | Jul 15 – Nov 4 |
Plant 0.1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| 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
171 days in Cass County
Growing Tips for Cass 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 →
Coreopsis in Other Locations
Frequently Asked Questions
When should I plant Coreopsis in Cass County, MI?
Cass County is in Zone 6a with an average last frost of April 29. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cass County, MI?
Cass County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is April 29 and first fall frost is October 17.
When should I plant Coreopsis in Cass County, MI?
In Cass County, MI, plant Coreopsis after the last frost (around April 29) and before the first frost (around October 17). Best results when soil holds above 50°F.
What growing zone is Cass County, MI for Coreopsis?
Cass 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 Cass County's climate?
Yes — Coreopsis grows well in Cass County's temperate climate. Cass County averages a 171-day frost-free season, with last frost around April 29 and first frost around October 17.
Your Cass County Garden Planner — Free
A 22-page printable planner built for Cass 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.