When to plant Cosmos in Rice County, MN
Rice County's climate puts the Cosmos spring window between May 7 and May 28. be cautious and check the 10-day forecast before planting tender crops.
When to Plant Cosmos in Rice County, MN
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.
Rice County, Minnesota is in USDA Zone 4b. The average last spring frost is April 30 and the first fall frost is October 7, giving you a growing season of approximately 160 days.
At an elevation of 873 feet, Rice County receives approximately 36.9 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.
Rice County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Cosmos Planting Timeline — Rice County, MN
Cosmos Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 2 | Apr 2 – Apr 16 |
| Transplant Outdoors | May 7 | May 7 – May 21 |
| Direct Sow | May 7 | May 7 – May 28 |
| Bloom | July 16 | Jul 16 – Oct 8 |
Plant 0.3" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| 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 4b
📆 Growing Season
160 days in Rice County
Growing Tips for Rice 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 Rice County, MN?
Rice County is in Zone 4b with an average last frost of April 30. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rice County, MN?
Rice County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is April 30 and first fall frost is October 7.
When should I plant Cosmos in Rice County, MN?
In Rice County, MN, plant Cosmos after the last frost (around April 30) and before the first frost (around October 7). Best results when soil holds above 50°F.
What growing zone is Rice County, MN for Cosmos?
Rice County sits in USDA Zone 4b. Cosmos grows reliably in zones 2a through 11b, so it's a good fit here.
Can Cosmos grow in Rice County's climate?
Yes — Cosmos grows well in Rice County's temperate climate. Rice County averages a 160-day frost-free season, with last frost around April 30 and first frost around October 7.
Your Rice County Garden Planner — Free
A 22-page printable planner built for Rice County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.