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When to Plant Sunflower in Scott County, MO

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.

Scott County, Missouri is in USDA Zone 6b. The average last spring frost is April 9 and the first fall frost is October 24, giving you a growing season of approximately 198 days.

At an elevation of 880 feet, Scott County receives approximately 34.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Sunflower during the growing season.

Scott County, MO (Zone 6b) Moderate season
198 days
Last Spring Frost April 9
198 growing days
First Fall Frost October 24

Scott County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (63 days to spare)
Start indoors: Feb 7 Transplant: Apr 18 🍅 Harvest: Jun 27 – Aug 15
Recommended (50%) ✓ Fits season (65 days to spare)
Start indoors: Feb 12 Transplant: Apr 23 🍅 Harvest: Jul 2 – Aug 20
Safe Start (90%) ✓ Fits season (63 days to spare)
Start indoors: Feb 26 Transplant: May 7 🍅 Harvest: Jul 16 – Sep 3

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.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.7″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Sunflower needs ~1,169 GDD — county provides 2,722 GDD Excellent fit

Sunflower Planting Timeline โ€” Scott County, MO

Sunflower Planting Calendar

Activity When Date Range
Start Indoors February 12 Feb 12 โ€“ Feb 26
Transplant Outdoors April 23 Apr 23 โ€“ May 7
Direct Sow April 16 Apr 16 โ€“ May 7
Harvest July 2 Jul 2 โ€“ Aug 20

Plant 1" deep ยท 18" apart ยท Rows 30" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March โ€”
April Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June โ€”
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Low โ€” drought tolerant

Days to Maturity

70โ€“100 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 6b

Growing Season

198 days

Growing Tips for Scott 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

  • Potatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Sunflower in Scott County, MO?

Scott County is in Zone 6b with an average last frost of April 9. Plan your Sunflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Scott County, MO?

Scott County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 9 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Scott County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Scott County, MO. Local conditions may vary. Last updated: April 2026.