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When to Plant Sunflower in Volusia County, FL

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.

Volusia County, Florida is in USDA Zone 9a. The average last spring frost is February 3 and the first fall frost is December 21, giving you a growing season of approximately 321 days.

At an elevation of 382 feet, Volusia County receives approximately 54.8 inches of rainfall annually with predominantly sand soil. Summer highs average 95ยฐF, so Sunflower may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” 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.

Volusia County, FL (Zone 9a) Year-round
321 days
Last Spring Frost February 3
321 growing days
First Fall Frost December 21

Volusia County Soil Profile

Soil Type

Sand

Soil pH

5-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (206 days to spare)
Start indoors: Dec 8 Transplant: Jan 26 🍅 Harvest: Apr 6 – May 25
Recommended (50%) ✓ Fits season (195 days to spare)
Start indoors: Dec 23 Transplant: Feb 10 🍅 Harvest: Apr 21 – Jun 9
Safe Start (90%) ✓ Fits season (172 days to spare)
Start indoors: Jan 20 Transplant: Mar 10 🍅 Harvest: May 19 – Jul 7

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 Volusia County

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

Soil pH

Your soil pH (5.0โ€“6.3) is more acidic than Sunflower prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Volusia County warms quickly in spring but drains fast. Sunflower will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (1.4%). Add 2-3 inches of compost before planting Sunflower.

How to Plant Sunflower

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

Succession Planting Sunflower

5
successive plantings in your 321-day season

Sow every 8 weeks. Last sowing by Sep 12 to harvest before frost.

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
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

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€” 2.5" 0" โ„๏ธ Dormant
Feb 2.2" 2.7" 0" โœ… Rainfall sufficient
Mar 2.2" 3" 0" โœ… Rainfall sufficient
Apr 2.2" 2.9" 0" โœ… Rainfall sufficient
May 2.2" 4" 0" โœ… Rainfall sufficient
Jun 2.2" 7.5" 0" โœ… Rainfall sufficient
Jul 2.2" 8.6" 0" โœ… Rainfall sufficient
Aug 2.2" 8.4" 0" โœ… Rainfall sufficient
Sep 2.2" 6.1" 0" โœ… Rainfall sufficient
Oct 2.2" 4.8" 0" โœ… Rainfall sufficient
Nov 2.2" 2" 0.2" ๐Ÿ’ง Light watering
Dec 2.2" 2.3" 0" โœ… Rainfall sufficient

Water needs are for active growing months only (Febโ€“Dec in Volusia 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 ~1,806 GDD — county provides 6,842 GDD Excellent fit

Sunflower Planting Timeline โ€” Volusia County, FL

Sunflower Planting Calendar

Activity When Date Range
Start Indoors December 23 Dec 23 โ€“ Jan 6
Transplant Outdoors February 10 Feb 10 โ€“ Feb 24
Direct Sow February 3 Feb 3 โ€“ Feb 24
Harvest April 21 Apr 21 โ€“ Jun 9

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

Month-by-Month Timeline

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

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 9a

๐Ÿ“† Growing Season

321 days in Volusia County

Growing Tips for Sunflower in Volusia County

Direct sow Sunflower outdoors after February 03 in Volusia County when soil has warmed and frost danger has passed.

Sandy soil in Volusia County dries quickly โ€” mulch Sunflower with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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 Volusia County, FL?

Volusia County is in Zone 9a with an average last frost of February 3. Plan your Sunflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Volusia County, FL?

Volusia County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is February 3 and first fall frost is December 21.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Volusia County gardeners in Zone 9a 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 Volusia County, FL. Local conditions may vary. Last updated: April 2026.