When to Plant Cosmos in Morgan County, OH
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.
Morgan County, Ohio is in USDA Zone 6b. The average last spring frost is April 27 and the first fall frost is October 20, giving you a growing season of approximately 176 days.
At an elevation of 1,205 feet, Morgan County receives approximately 37 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Cosmos during the growing season.
Morgan County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Cosmos Planting Timeline — Morgan County, OH
Cosmos Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 30 | Mar 30 – Apr 13 |
| Transplant Outdoors | April 27 | Apr 27 – May 11 |
| Direct Sow | April 27 | Apr 27 – May 18 |
| Bloom | July 6 | Jul 6 – Oct 19 |
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 6b
📆 Growing Season
176 days in Morgan County
Growing Tips for Morgan 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 Morgan County, OH?
Morgan County is in Zone 6b with an average last frost of April 27. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.
What planting zone is Morgan County, OH?
Morgan County, Ohio is in USDA Hardiness Zone 6b. The average last spring frost is April 27 and first fall frost is October 20.
Your Morgan County Garden Planner — Free
A 22-page printable planner built for Morgan County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.