When to Plant Sunflower in Douglas County, KS
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.
Douglas County, Kansas is in USDA Zone 6a. The average last spring frost is April 12 and the first fall frost is October 25, giving you a growing season of approximately 196 days.
At an elevation of 494 feet, Douglas County receives approximately 27.7 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Sunflower during the growing season.
Douglas County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.6
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Douglas County
How your county's soil matches Sunflower's growing requirements.
Soil pH
Your soil pH (6.5–7.6) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Douglas County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.2%). Annual compost additions will help Sunflower.
How to Plant Sunflower
Succession Planting Sunflower
Sow every 8 weeks. Last sowing by Jul 17 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Sunflower Planting Timeline — Douglas County, KS
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 15 | Feb 15 – Mar 1 |
| Transplant Outdoors | April 26 | Apr 26 – May 10 |
| Direct Sow | April 19 | Apr 19 – May 10 |
| Harvest | July 5 | Jul 5 – Aug 23 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
196 days in Douglas County
Growing Tips for Sunflower in Douglas County
Direct sow Sunflower outdoors after April 12 in Douglas County when soil has warmed and frost danger has passed.
Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
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
Level Up Your Garden
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Douglas County, KS?
Douglas County is in Zone 6a with an average last frost of April 12. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Douglas County, KS?
Douglas County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 12 and first fall frost is October 25.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Douglas County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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