Blog

When to plant Sunflower in Lorida, FL

Plant Sunflower in Lorida after January 29; the prime window is January 1–January 22.

When to Plant Sunflower in Lorida, FL

Highlands County, Florida Zone 9b June

Highlands County, Florida gardeners: here's your June plan

Each item below is timed to Highlands County, Florida's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost January 29
Avg. first frost December 20
Soil temp (4") 88°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
  1. It's harvest week for sunflower

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

July will be here before you know it — start on
  • First harvests: sunflower

Instant PDF download. No spam, unsubscribe any time.

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.

Lorida, Florida is in USDA Zone 9b. The average last spring frost is January 29 and the first fall frost is December 20, giving you a growing season of approximately 325 days.

At an elevation of 111 feet, Highlands County receives approximately 57.6 inches of rainfall annually with predominantly sand soil. Summer highs average 95°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
Lorida, FL (Zone 9b) Year-round
325 days
Last Spring Frost January 29
325 growing days
First Fall Frost December 20

Lorida Soil Profile

Soil Type

Sand

Soil pH

4.9-5.8

Drainage

Well Drained

Sunflower Planting Risk Windows

Early Start (70% safe) ✓ Fits season (97 days to spare)
Start indoors: Jan 1 Transplant: Dec 25 🌸 Bloom: Mar 19 – Sep 3
Recommended (50%) ✓ Fits season (101 days to spare)
Start indoors: Jan 8 Transplant: Jan 1 🌸 Bloom: Mar 26 – Sep 10
Safe Start (90%) ✓ Fits season (73 days to spare)
Start indoors: Feb 9 Transplant: Feb 2 🌸 Bloom: Apr 27 – Oct 12

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 Lorida

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

Soil pH

Your soil pH (4.9–5.8) is more acidic than Sunflower prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Highlands 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 (1.6%). 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 325-day season

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

Sunflower Water Budget

Plant needs
0.5″/week
Rainfall provides
0.7″/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 2.2" 2.4" 0" ✅ Rainfall sufficient
Feb 2.2" 3.1" 0" ✅ Rainfall sufficient
Mar 2.2" 3.6" 0" ✅ Rainfall sufficient
Apr 2.2" 2.3" 0" ✅ Rainfall sufficient
May 2.2" 3.8" 0" ✅ Rainfall sufficient
Jun 2.2" 8.5" 0" ✅ Rainfall sufficient
Jul 2.2" 7.5" 0" ✅ Rainfall sufficient
Aug 2.2" 9.1" 0" ✅ Rainfall sufficient
Sep 2.2" 8" 0" ✅ Rainfall sufficient
Oct 2.2" 5.1" 0" ✅ Rainfall sufficient
Nov 2.2" 2.1" 0.1" 💧 Light watering
Dec 2.2" 2.3" 0" ✅ Rainfall sufficient

Water needs are for active growing months only (Jan–Dec in Highlands 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 ~1,806 GDD — county provides 6,927 GDD Excellent fit

Sunflower Planting Timeline — Lorida, FL

Sunflower Planting Calendar

Activity When Date Range
Start Indoors January 8 Jan 8 – Jan 22
Transplant Outdoors January 1 Jan 1 – Jan 15
Direct Sow January 1 Jan 1 – Jan 22
Bloom March 26 Mar 26 – Sep 10

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

Month-by-Month Timeline

MonthActivities
January Start Indoors Transplant Outdoors Direct Sow
February
March Bloom
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

325 days in Highlands County

Growing Tips for Sunflower in Lorida

Direct sow Sunflower outdoors after January 29 in Highlands County when soil has warmed and frost danger has passed.

Sandy soil in Highlands County dries quickly — 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 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 →

When should I plant Sunflower in Lorida, FL?

In Lorida, FL, plant Sunflower after the last frost (around January 29) and before the first frost (around December 20). Best results when soil holds above 50°F.

What growing zone is Lorida, FL for Sunflower?

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

Can Sunflower grow in Lorida's climate?

Yes — Sunflower grows well in Lorida's temperate climate. Lorida averages a 326-day frost-free season, with last frost around January 29 and first frost around December 20.

🌱

Your Highlands County Garden Planner — Free

A 22-page printable planner built for Highlands 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Highlands County, FL. Local conditions may vary. Last updated: June 2026.