When to plant Sunflower in Nassau County, FL
For Sunflower in Nassau County, the safe spring window opens around January 24 and closes around February 14. Last expected frost is February 14, first fall frost December 1, giving a 291-day growing season.
When to Plant Sunflower in Nassau 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.
Nassau County, Florida is in USDA Zone 9a. The average last spring frost is February 14 and the first fall frost is December 1, giving you a growing season of approximately 290 days.
At an elevation of 408 feet, Nassau County receives approximately 57.9 inches of rainfall annually with predominantly sand soil. Summer highs average 101°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.
Nassau County Soil Profile
Soil Type
Sand
Soil pH
5.2-5.8
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 | — | 2.8" | 0" | ❄️ Dormant |
| Feb | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Mar | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Apr | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| May | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Jun | 4.3" | 6.6" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 7.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 8.7" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 7.9" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 5.3" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Dec | 4.3" | 2.5" | 1.8" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in Nassau County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower Planting Timeline — Nassau County, FL
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 24 | Jan 24 – Feb 7 |
| Transplant Outdoors | January 24 | Jan 24 – Feb 7 |
| Direct Sow | January 24 | Jan 24 – Feb 14 |
| Bloom | April 18 | Apr 18 – Sep 19 |
Plant 1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Transplant Outdoors Direct Sow |
| February | Start Indoors Transplant Outdoors Direct Sow |
| 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
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
290 days in Nassau County
Growing Tips for Nassau 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
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Nassau County, FL?
Nassau County is in Zone 9a with an average last frost of February 14. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Nassau County, FL?
Nassau County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is February 14 and first fall frost is December 1.
When should I plant Sunflower in Nassau County, FL?
In Nassau County, FL, plant Sunflower after the last frost (around February 14) and before the first frost (around December 1). Best results when soil holds above 50°F.
What growing zone is Nassau County, FL for Sunflower?
Nassau 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 Nassau County's climate?
Yes — Sunflower grows well in Nassau County's temperate climate. Nassau County averages a 291-day frost-free season, with last frost around February 14 and first frost around December 1.
Your Nassau County Garden Planner — Free
A 22-page printable planner built for Nassau 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.