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When to plant Watermelon in Nassau County, FL

Nassau County gardeners should plant Watermelon between February 14 and March 7 in spring. With Nassau County's Zone 9a climate (last frost February 14), Watermelon needs 70–100 days to mature — plant by August 23 for a full harvest.

When to Plant Watermelon in Nassau County, FL

Watermelon

Watermelon is a sprawling vine crop that produces sweet, juicy fruits in hot weather. Varieties range from personal-sized icebox types to 50-pound giants.

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 Watermelon may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Watermelon will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Watermelon root diseases.

Nassau County, FL (Zone 9a) Year-round
290 days
Last Spring Frost February 14
290 growing days
First Fall Frost December 1

Nassau County Soil Profile

Soil Type

Sand

Soil pH

5.2-5.8

Drainage

Well Drained

How Much Watermelon to Grow

15-20 lbs
Average yield per plant
1
Plants per person
2 sq ft
Space per person

For a family of 4, plant approximately 4 watermelon plants in about 8 sq ft. In Nassau County's 290-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Monthly Watering Guide for Watermelon

Watermelon needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Watermelon 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.

Watermelon Planting Timeline — Nassau County, FL

Watermelon Planting Calendar

Activity When Date Range
Start Indoors January 17 Jan 17 – Jan 31
Transplant Outdoors February 21 Feb 21 – Mar 7
Direct Sow February 14 Feb 14 – Mar 7
Harvest May 2 May 2 – Jun 20

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 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

Start seeds indoors 3-4 weeks early or direct sow after soil is warm. Plant on mounds with plenty of space. Check ripeness by looking for a yellow ground spot and dull thump when tapped.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Watermelon in Nassau County, FL?

Nassau County is in Zone 9a with an average last frost of February 14. Plan your Watermelon 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 Watermelon in Nassau County, FL?

In Nassau County, FL, plant Watermelon 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 Watermelon?

Nassau County sits in USDA Zone 9a. Watermelon grows reliably in zones 4a through 11b, so it's a good fit here.

Can Watermelon grow in Nassau County's climate?

Yes — Watermelon 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.

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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.

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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 Nassau County, FL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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