When to plant Cosmos in Genesee County, MI
For Genesee County, gardeners: plant Cosmos April 28 through May 19 once soil reads 50°F.
When to Plant Cosmos in Genesee County, MI
Cosmos (Cosmos bipinnatus) is an airy, feathery-foliaged cottage garden annual from Mexico that thrives on neglect. It produces delicate daisy-like blooms in shades of pink, white, and magenta from midsummer until frost. Cosmos is a prolific self-sower — once established in a garden it often returns year after year without replanting. Excellent habitat plant for beneficial insects.
Genesee County, Michigan is in USDA Zone 6a. The average last spring frost is April 28 and the first fall frost is October 17, giving you a growing season of approximately 172 days.
At an elevation of 1,023 feet, Genesee County receives approximately 39.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Cosmos to ensure they mature before fall.
Genesee County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Cosmos Planting Timeline — Genesee County, MI
Cosmos Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 31 | Mar 31 – Apr 14 |
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
| Direct Sow | April 28 | Apr 28 – May 19 |
| Bloom | July 7 | Jul 7 – Oct 13 |
Plant 0.3" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–8 · Your soil: N/A
🗺️ USDA Zone
Zone 6a
📆 Growing Season
172 days in Genesee County
Growing Tips for Genesee County
Direct-sow after last frost; cosmos germinates readily at 65-80°F in 7-10 days. Avoid rich soil — excess fertility produces lush foliage at the expense of blooms. Cosmos tolerates poor, dry soil exceptionally well. Pinch seedlings at 8 inches to encourage branching. Self-sows freely; allow some seed heads to mature and drop for a no-fuss perennial effect in warm climates.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Cosmos in Other Locations
Frequently Asked Questions
When should I plant Cosmos in Genesee County, MI?
Genesee County is in Zone 6a with an average last frost of April 28. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.
What planting zone is Genesee County, MI?
Genesee County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is April 28 and first fall frost is October 17.
When should I plant Cosmos in Genesee County, MI?
In Genesee County, MI, plant Cosmos after the last frost (around April 28) and before the first frost (around October 17). Best results when soil holds above 50°F.
What growing zone is Genesee County, MI for Cosmos?
Genesee County sits in USDA Zone 6a. Cosmos grows reliably in zones 2a through 11b, so it's a good fit here.
Can Cosmos grow in Genesee County's climate?
Yes — Cosmos grows well in Genesee County's temperate climate. Genesee County averages a 172-day frost-free season, with last frost around April 28 and first frost around October 17.
Your Genesee County Garden Planner — Free
A 22-page printable planner built for Genesee 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.