When to plant Bachelor's Button in St. Clair County, MI
St. Clair County's spring Bachelor's Button window runs March 30 through April 20. time plantings around the expected last-frost window for best survival. A second sowing from September 15 to September 29 extends the harvest into fall.
When to Plant Bachelor's Button in St. Clair County, MI
Bachelor's Button (Centaurea cyanus), also called cornflower, is a carefree cool-season annual best known for its vivid cobalt-blue flowers — one of the truest blues in the annual garden. It tolerates light frosts, self-seeds prolifically, and thrives in poor to average soils. A traditional cut flower and pollinator magnet, it has been cultivated in gardens for centuries.
St. Clair County, Michigan is in USDA Zone 6a. The average last spring frost is April 27 and the first fall frost is October 27, giving you a growing season of approximately 183 days.
At an elevation of 1,065 feet, St. Clair County receives approximately 38.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Bachelor's Button during the growing season.
St. Clair County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Bachelor's Button Planting Timeline — St. Clair County, MI
Bachelor's Button Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 16 | Mar 16 – Mar 30 |
| Transplant Outdoors | April 27 | Apr 27 – May 11 |
| Direct Sow | March 30 | Mar 30 – Apr 20 |
| Bloom | June 29 | Jun 29 – Sep 14 |
| Fall Sowing | September 15 | Sep 15 – Sep 29 |
Plant 0.3" deep · 12" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Fall Sowing Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 6a
📆 Growing Season
183 days in St. Clair County
Growing Tips for St. Clair County
Direct-sow in early spring as soon as soil can be worked; seeds need a brief cold period for best germination (refrigerate for a few days before planting if spring arrives quickly). In zones 6+, fall-sow for the earliest spring bloom. Thin to 12 inches; do not over-fertilize — too much nitrogen produces foliage at the expense of flowers. Deadhead to prolong blooming or allow self-seeding for a naturalized colony.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Bachelor's Button in Other Locations
Frequently Asked Questions
When should I plant Bachelor's Button in St. Clair County, MI?
St. Clair County is in Zone 6a with an average last frost of April 27. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Clair County, MI?
St. Clair County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is April 27 and first fall frost is October 27.
When should I plant Bachelor's Button in St. Clair County, MI?
In St. Clair County, MI, plant Bachelor's Button after the last frost (around April 27) and before the first frost (around October 27). Best results when soil holds above 50°F.
What growing zone is St. Clair County, MI for Bachelor's Button?
St. Clair County sits in USDA Zone 6a. Bachelor's Button grows reliably in zones 2a through 11b, so it's a good fit here.
Can Bachelor's Button grow in St. Clair County's climate?
Yes — Bachelor's Button grows well in St. Clair County's temperate climate. St. Clair County averages a 183-day frost-free season, with last frost around April 27 and first frost around October 27.
Your St. Clair County Garden Planner — Free
A 22-page printable planner built for St. Clair 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.