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When to plant Sunflower in Sumter County, FL

Sumter County gardeners should plant Sunflower between January 9 and January 30 in spring. With Sumter County's Zone 9b climate (last frost February 6), Sunflower needs 70–100 days to mature — plant by August 28 for a full harvest.

When to Plant Sunflower in Sumter County, FL

Sumter County, Florida Zone 9b June

This month in Sumter County, Florida

Welcome to June in Zone 9b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost February 6
Avg. first frost December 6
Soil temp (4") 85°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Collect sunflower at their peak

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

Looking ahead to July
  • First harvests: sunflower

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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.

Sumter County, Florida is in USDA Zone 9b. The average last spring frost is February 6 and the first fall frost is December 6, giving you a growing season of approximately 303 days.

At an elevation of 463 feet, Sumter County receives approximately 60.9 inches of rainfall annually with predominantly sand soil. Summer highs average 96°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
Sumter County, FL (Zone 9b) Year-round
303 days
Last Spring Frost February 6
303 growing days
First Fall Frost December 6

Sumter County Soil Profile

Soil Type

Sand

Soil pH

5-6.1

Drainage

Well Drained

Sunflower Planting Risk Windows

Early Start (70% safe) ✓ Fits season (82 days to spare)
Start indoors: Jan 3 Transplant: Dec 27 🌸 Bloom: Mar 21 – Sep 5
Recommended (50%) ✓ Fits season (79 days to spare)
Start indoors: Jan 16 Transplant: Jan 9 🌸 Bloom: Apr 3 – Sep 18
Safe Start (90%) ✓ Fits season (72 days to spare)
Start indoors: Feb 11 Transplant: Feb 4 🌸 Bloom: Apr 29 – Oct 14

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 Sumter County

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

Soil pH

Your soil pH (5.0–6.1) is more acidic than Sunflower prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Sumter 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 (1.4%). Add 2-3 inches of compost before planting Sunflower.

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Sunflower

5
successive plantings in your 303-day season

Sow every 8 weeks. Last sowing by Aug 28 to harvest before frost.

Sunflower Water Budget

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

Water stress score is 6/10 — 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 3.2" 0" ❄️ Dormant
Feb 2.2" 3.3" 0" ✅ Rainfall sufficient
Mar 2.2" 3.6" 0" ✅ Rainfall sufficient
Apr 2.2" 2.7" 0" ✅ Rainfall sufficient
May 2.2" 4.3" 0" ✅ Rainfall sufficient
Jun 2.2" 8" 0" ✅ Rainfall sufficient
Jul 2.2" 8.7" 0" ✅ Rainfall sufficient
Aug 2.2" 8.5" 0" ✅ Rainfall sufficient
Sep 2.2" 7.6" 0" ✅ Rainfall sufficient
Oct 2.2" 6.1" 0" ✅ Rainfall sufficient
Nov 2.2" 2.6" 0" ✅ Rainfall sufficient
Dec 2.2" 2.5" 0" ✅ Rainfall sufficient

Water needs are for active growing months only (Feb–Dec in Sumter County). Supplement amounts are based on average rainfall — 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" — every day above 50°F 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 ~1,870 GDD — county provides 6,688 GDD Excellent fit

Sunflower Planting Timeline — Sumter County, FL

Sunflower Planting Calendar

Activity When Date Range
Start Indoors January 16 Jan 16 – Jan 30
Transplant Outdoors January 9 Jan 9 – Jan 23
Direct Sow January 9 Jan 9 – Jan 30
Bloom April 3 Apr 3 – Sep 18

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9b

📆 Growing Season

303 days in Sumter County

Growing Tips for Sunflower in Sumter County

Direct sow Sunflower outdoors after February 06 in Sumter County when soil has warmed and frost danger has passed.

Sandy soil in Sumter County dries quickly — 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 96°F in Sumter 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 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 Sumter County, FL?

Sumter County is in Zone 9b with an average last frost of February 6. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sumter County, FL?

Sumter County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is February 6 and first fall frost is December 6.

When should I plant Sunflower in Sumter County, FL?

In Sumter County, FL, plant Sunflower after the last frost (around February 6) and before the first frost (around December 6). Best results when soil holds above 50°F.

What growing zone is Sumter County, FL for Sunflower?

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

Can Sunflower grow in Sumter County's climate?

Yes — Sunflower grows well in Sumter County's temperate climate. Sumter County averages a 304-day frost-free season, with last frost around February 6 and first frost around December 6.

🌱

Your Sumter County Garden Planner — Free

A 22-page printable planner built for Sumter County (Zone 9b). 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 Sumter County, FL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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