When to Plant Sunflower in Otsego County, MI
Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.
Otsego County, Michigan is in USDA Zone 4b. The average last spring frost is May 8 and the first fall frost is October 13, giving you a growing season of approximately 158 days.
At an elevation of 1,278 feet, Otsego County receives approximately 35.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Sunflower to ensure they mature before fall.
Otsego County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7.1
Drainage
Well Drained
Monthly Watering Guide for Sunflower
Sunflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Sunflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | — | 2.9" | 0" | ❄️ Dormant |
| May | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Aug | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Sep | 4.3" | 3" | 1.3" | 💧 Light watering |
| Oct | 4.3" | 3" | 1.3" | 💧 Light watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Otsego County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower Planting Timeline — Otsego County, MI
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | May 29 | May 29 – Jun 12 |
| Direct Sow | May 22 | May 22 – Jun 12 |
| Harvest | August 7 | Aug 7 – Sep 25 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 4b
📆 Growing Season
158 days in Otsego County
Growing Tips for Otsego County
Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Otsego County, MI?
Otsego County is in Zone 4b with an average last frost of May 8. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Otsego County, MI?
Otsego County, Michigan is in USDA Hardiness Zone 4b. The average last spring frost is May 8 and first fall frost is October 13.
Plan Your Garden with Confidence
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