Blog

When to Plant Sunflower in Madison County, OH

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.

Madison County, Ohio is in USDA Zone 5b. The average last spring frost is April 22 and the first fall frost is October 20, giving you a growing season of approximately 181 days.

At an elevation of 674 feet, Madison County receives approximately 35.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Sunflower during the growing season.

Madison County, OH (Zone 5b) Moderate season
181 days
Last Spring Frost April 22
181 growing days
First Fall Frost October 20

Madison County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7.1

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 โ€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 1.6" 0" โ„๏ธ Dormant
Mar โ€” 2.5" 0" โ„๏ธ Dormant
Apr 4.3" 3.3" 1" ๐Ÿ’ง Light watering
May 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Jun 4.3" 4.7" 0" โœ… Rainfall sufficient
Jul 4.3" 4.5" 0" โœ… Rainfall sufficient
Aug 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Sep 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Oct 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Nov โ€” 2.5" 0" โ„๏ธ Dormant
Dec โ€” 1.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Madison County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Sunflower Planting Timeline โ€” Madison County, OH

Sunflower Planting Calendar

Activity When Date Range
Start Indoors February 25 Feb 25 โ€“ Mar 11
Transplant Outdoors May 6 May 6 โ€“ May 20
Direct Sow April 29 Apr 29 โ€“ May 20
Harvest July 15 Jul 15 โ€“ Sep 2

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

Low โ€” drought tolerant

๐Ÿ“… Days to Maturity

70โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

181 days in Madison County

Growing Tips for Madison 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Madison County, OH?

Madison County is in Zone 5b with an average last frost of April 22. Plan your Sunflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Madison County, OH?

Madison County, Ohio is in USDA Hardiness Zone 5b. The average last spring frost is April 22 and first fall frost is October 20.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Madison County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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