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When to Plant Sunflower in Okeechobee 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.

Okeechobee County, Florida is in USDA Zone 9b. The average last spring frost is January 25 and the first fall frost is December 20, giving you a growing season of approximately 329 days.

At an elevation of 139 feet, Okeechobee County receives approximately 49.6 inches of rainfall annually with predominantly sand soil. Summer highs average 101ยฐF, 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.

Okeechobee County, FL (Zone 9b) Year-round
329 days
Last Spring Frost January 25
329 growing days
First Fall Frost December 20

Okeechobee County Soil Profile

Soil Type

Sand

Soil pH

5.2-5.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (197 days to spare)
Start indoors: Dec 8 Transplant: Jan 26 🍅 Harvest: Apr 6 – May 25
Recommended (50%) ✓ Fits season (203 days to spare)
Start indoors: Dec 14 Transplant: Feb 1 🍅 Harvest: Apr 12 – May 31
Safe Start (90%) ✓ Fits season (181 days to spare)
Start indoors: Jan 10 Transplant: Feb 28 🍅 Harvest: May 9 – Jun 27

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 Okeechobee County

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

Soil pH

Your soil pH (5.2โ€“5.8) is more acidic than Sunflower prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Sunflower.

Organic Matter

Organic matter is low (1.7%). 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 329-day season

Sow every 8 weeks. Last sowing by Sep 11 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.6″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 66 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 2.2" 2.5" 0" โœ… Rainfall sufficient
Feb 2.2" 2.4" 0" โœ… Rainfall sufficient
Mar 2.2" 3.2" 0" โœ… Rainfall sufficient
Apr 2.2" 2.2" 0" โœ… Rainfall sufficient
May 2.2" 3.5" 0" โœ… Rainfall sufficient
Jun 2.2" 6.8" 0" โœ… Rainfall sufficient
Jul 2.2" 6.9" 0" โœ… Rainfall sufficient
Aug 2.2" 7.6" 0" โœ… Rainfall sufficient
Sep 2.2" 6.6" 0" โœ… Rainfall sufficient
Oct 2.2" 3.5" 0" โœ… Rainfall sufficient
Nov 2.2" 2.2" 0" โœ… Rainfall sufficient
Dec 2.2" 2.1" 0.1" ๐Ÿ’ง Light watering

Water needs are for active growing months only (Janโ€“Dec in Okeechobee 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 ~2,189 GDD — county provides 8,497 GDD Excellent fit

Sunflower Planting Timeline โ€” Okeechobee County, FL

Sunflower Planting Calendar

Activity When Date Range
Start Indoors December 14 Dec 14 โ€“ Dec 28
Transplant Outdoors February 1 Feb 1 โ€“ Feb 15
Direct Sow January 25 Jan 25 โ€“ Feb 15
Harvest April 12 Apr 12 โ€“ May 31

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

Month-by-Month Timeline

MonthActivities
January Direct Sow
February Transplant Outdoors Direct Sow
March โ€”
April Harvest
May Harvest
June โ€”
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 Only during dry spells

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 9b

๐Ÿ“† Growing Season

329 days in Okeechobee County

Growing Tips for Sunflower in Okeechobee County

Direct sow Sunflower outdoors after January 25 in Okeechobee County when soil has warmed and frost danger has passed.

Sandy soil in Okeechobee 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.

With summer highs reaching 101ยฐF in Okeechobee County, provide afternoon shade for Sunflower and water deeply in the morning.

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 Okeechobee County, FL?

Okeechobee County is in Zone 9b with an average last frost of January 25. Plan your Sunflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Okeechobee County, FL?

Okeechobee County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is January 25 and first fall frost is December 20.

๐ŸŒฑ

Plan Your Garden with Confidence

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