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When to plant Sunflower in Washington County, FL

Washington County's spring Sunflower window runs February 12 through March 5. aim for a steady week of warm soil before planting.

When to Plant Sunflower in Washington County, FL

Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.

Washington County, Florida is in USDA Zone 9a. The average last spring frost is March 5 and the first fall frost is November 20, giving you a growing season of approximately 260 days.

At an elevation of 196 feet, Washington County receives approximately 50.6 inches of rainfall annually with predominantly sand soil. Summer highs average 97°F, so Sunflower may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Sunflower will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Washington County, FL (Zone 9a) Long season
260 days
Last Spring Frost March 5
260 growing days
First Fall Frost November 20

Washington County Soil Profile

Soil Type

Sand

Soil pH

4.8-5.9

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 2" 0" ❄️ Dormant
Feb 2.8" 0" ❄️ Dormant
Mar 4.3" 2.5" 1.8" 💧 Light watering
Apr 4.3" 2.2" 2.1" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 6.8" 0" ✅ Rainfall sufficient
Jul 4.3" 8.5" 0" ✅ Rainfall sufficient
Aug 4.3" 6.5" 0" ✅ Rainfall sufficient
Sep 4.3" 7.3" 0" ✅ Rainfall sufficient
Oct 4.3" 4" 0.3" 💧 Light watering
Nov 4.3" 2.1" 2.2" 🚿 Regular watering
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Washington County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Sunflower Planting Timeline — Washington County, FL

Sunflower Planting Calendar

Activity When Date Range
Start Indoors February 12 Feb 12 – Feb 26
Transplant Outdoors February 12 Feb 12 – Feb 26
Direct Sow February 12 Feb 12 – Mar 5
Bloom May 7 May 7 – Oct 8

Plant 1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors Transplant Outdoors Direct Sow
March Direct Sow
April
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
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 9a

📆 Growing Season

260 days in Washington County

Growing Tips for Washington County

Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Pole_beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Washington County, FL?

Washington County is in Zone 9a with an average last frost of March 5. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Washington County, FL?

Washington County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is March 5 and first fall frost is November 20.

When should I plant Sunflower in Washington County, FL?

In Washington County, FL, plant Sunflower after the last frost (around March 5) and before the first frost (around November 20). Best results when soil holds above 50°F.

What growing zone is Washington County, FL for Sunflower?

Washington County sits in USDA Zone 9a. Sunflower grows reliably in zones 2a through 11b, so it's a good fit here.

Can Sunflower grow in Washington County's climate?

Yes — Sunflower grows well in Washington County's temperate climate. Washington County averages a 260-day frost-free season, with last frost around March 5 and first frost around November 20.

🌱

Your Washington County Garden Planner — Free

A 22-page printable planner built for Washington County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Washington County, FL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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