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When to Plant Sunflower in Dare County, NC

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.

Dare County, North Carolina is in USDA Zone 8a. The average last spring frost is March 23 and the first fall frost is November 21, giving you a growing season of approximately 243 days.

At an elevation of 787 feet, Dare County receives approximately 51.9 inches of rainfall annually with predominantly clay loam soil. Summer highs average 92ยฐF, providing good warmth for Sunflower during the growing season. Clay soil retains moisture well for Sunflower, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.

Dare County, NC (Zone 8a) Long season
243 days
Last Spring Frost March 23
243 growing days
First Fall Frost November 21

Dare County Soil Profile

Soil Type

Clay Loam

Soil pH

5.3-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (107 days to spare)
Start indoors: Jan 26 Transplant: Mar 30 🍅 Harvest: Jun 8 – Jul 27
Recommended (50%) ✓ Fits season (110 days to spare)
Start indoors: Feb 2 Transplant: Apr 6 🍅 Harvest: Jun 15 – Aug 3
Safe Start (90%) ✓ Fits season (112 days to spare)
Start indoors: Feb 21 Transplant: Apr 25 🍅 Harvest: Jul 4 – Aug 22

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 Dare County

How your county's soil matches Sunflower's growing requirements.

Soil pH

Your soil pH (5.3โ€“6.6) is more acidic than Sunflower prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

The clay loam soil in Dare County is excellent for Sunflower โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Sunflower.

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
30"
Between Rows

Succession Planting Sunflower

4
successive plantings in your 243-day season

Sow every 8 weeks. Last sowing by Aug 13 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Sunflower

Sunflower needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Sunflower Needs Rainfall You Supplement Action
Jan โ€” 3.9" 0" โ„๏ธ Dormant
Feb โ€” 4.5" 0" โ„๏ธ Dormant
Mar 2.2" 5.1" 0" โœ… Rainfall sufficient
Apr 2.2" 3.5" 0" โœ… Rainfall sufficient
May 2.2" 4.5" 0" โœ… Rainfall sufficient
Jun 2.2" 5" 0" โœ… Rainfall sufficient
Jul 2.2" 5.2" 0" โœ… Rainfall sufficient
Aug 2.2" 5.2" 0" โœ… Rainfall sufficient
Sep 2.2" 3.6" 0" โœ… Rainfall sufficient
Oct 2.2" 3.1" 0" โœ… Rainfall sufficient
Nov 2.2" 4.2" 0" โœ… Rainfall sufficient
Dec โ€” 4.1" 0" โ„๏ธ Dormant

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

Sunflower Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Sunflower needs ~1,615 GDD — county provides 4,617 GDD Excellent fit

Sunflower Planting Timeline โ€” Dare County, NC

Sunflower Planting Calendar

Activity When Date Range
Start Indoors February 2 Feb 2 โ€“ Feb 16
Transplant Outdoors April 6 Apr 6 โ€“ Apr 20
Direct Sow March 30 Mar 30 โ€“ Apr 20
Harvest June 15 Jun 15 โ€“ Aug 3

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

70โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

243 days in Dare County

Growing Tips for Sunflower in Dare County

Direct sow Sunflower outdoors after March 23 in Dare County when soil has warmed and frost danger has passed.

With Dare County's clay soil (32% clay), work in 3-4 inches of compost before planting Sunflower. Avoid tilling when soil is wet to prevent compaction.

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

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Dare County, NC?

Dare County is in Zone 8a with an average last frost of March 23. Plan your Sunflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Dare County, NC?

Dare County, North Carolina is in USDA Hardiness Zone 8a. The average last spring frost is March 23 and first fall frost is November 21.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Dare County gardeners in Zone 8a 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 Dare County, NC. Local conditions may vary. Last updated: April 2026.