Nassau County, in Florida, sits in USDA hardiness zone 9a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
On paper, mango, tomato, orange, and sweet potato all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring
Nassau County holds more than one microclimate.
Soils and elevations shift across Nassau County, so your frost dates and drainage aren't the county average. Enter your address and we'll score 1,112 plants against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Quick Facts
USDA Zones
9a
Last Frost (state avg.)
Jan 1 - Mar 15
First Frost (state avg.)
Nov 15 - never (south FL)
County Area
415K acres
Hardiness Zone Range
Growing Season
Zone maps are averages across Nassau County. Your yard's slope, trees, and frost pockets shift what actually grows — see your land's exact reading.
Soil in Nassau County
Across Nassau County, the ground is predominantly Spodosols, where Goldhead, Leon, and Boulogne are the most extensive named soil series. The soil is generally poorly drained with a fine sand surface. Topsoil pH runs about 4.6–6.2, strongly acidic. Rainfall drains through hydrologic group B/D soils.
Soil order
Spodosols
Drainage
Poorly drained
Hydric soils
52%
Soil still varies lot by lot — soil types explained.
What Grows in Nassau County
Plants matched to Nassau County's USDA zones 9a — each links to its full growing profile.
Growing Challenges in Florida
What an experienced grower plans around here — each one has a move.
Sandy soils drain too fast and hold few nutrients — frequent fertilization needed
Build organic matter relentlessly — compost and cover crops turn sand into soil that holds both water and food.
Humidity drives fungal diseases (powdery mildew, black spot, rust)
Space plants for airflow, water at the base in the morning, and choose resistant varieties — your extension office lists the proven ones.
Hurricane season (June-November) can destroy plantings
Favor wind-tough perennials, stake young trees properly, and keep fall crops in containers you can move ahead of a storm.
Nematodes are a serious pest in sandy FL soils
Summer solarization and crop-family rotation knock nematodes back — your extension office can confirm the species from a soil sample.
For cultivar selection, pest pressure, and planting-time guidance specific to Florida, the UF/IFAS Extension is the authoritative local source.
Safe to Grow Here?
What the federal record shows across Nassau County — and how to grow with it.
We checked the federal record across Nassau County — 327 documented sites across 6 of the 9 source types we track.
The most significant on record: 1 Superfund site. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
There's a meaningful federal record across Nassau County — worth a look before you plant food, not a reason to hold back from growing. Proximity to a documented site is information, not a diagnosis of any one yard. A soil test before new food beds is the sensible precaution here, and the map shows exactly which sites sit where, so you can see what's actually near you.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
Environmental Intelligence
Understanding what's nearby helps you make informed decisions about where and how to grow.
Sources Checked
across Nassau County
Severity Distribution
across Nassau County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Nassau County, PFAS runs higher than the national average — 3 sites nearby. That's not a problem with your land — it's information about it.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Nassau County
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,112 plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Your Specific Parcel Matters
Nassau County Average
- ●USDA Zones 9a
- ●Generic soil type for the area
- ●State-average frost dates
YOUR Parcel
- ✓Your exact hardiness zone
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Nassau County
Pull a site-specific report for your exact address in Nassau County, Florida — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Key Growing Facts for Nassau County, Florida
- USDA Hardiness Zones: 9a (USDA PHZM 2023)
- Last Spring Frost (state avg.): Jan 1 - Mar 15 (NOAA 30-Year Climate Normals)
- First Fall Frost (state avg.): Nov 15 - never (south FL) (NOAA 30-Year Climate Normals)
- County Land Area: 415K acres (US Census TIGER 2025)
Zone data: USDA ARS Plant Hardiness Zone Map 2023. Climate data: NOAA NCEI. County boundaries: US Census TIGER/Line 2025.
Frost dates here are the Nassau County average. Low spots and tree cover move them by days on any one yard — see your exact frost windows.
Frequently Asked Questions
What hardiness zone is Nassau County, Florida?
Nassau County sits in USDA hardiness zone 9a, per the USDA Plant Hardiness Zone Map 2023. Zones reflect average annual extreme minimum temperatures from 1991–2020 weather data.
When does frost risk typically end in Nassau County?
Nassau County follows Florida's statewide frost window: last spring frost around Jan 1 - Mar 15 and first fall frost around Nov 15 - never (south FL), per NOAA 30-year climate normals (1991–2020). Frost dates shift with elevation and local microclimate, so watch your own site's cold pockets.
What vegetables grow in Nassau County?
Nassau County's zone 9a supports a wide range — strong performers include Mango, Tomato, Orange, Sweet Potato, and Banana. What actually takes on any one site comes down to its soil, sun, and drainage, and we score each plant against the real conditions at your address.
Which hardiness zone is Nassau County, really?
Officially, Nassau County sits in USDA zone 9a (USDA PHZM 2023) — but a zone is a 30-year average of winter's coldest night across an area, and it can't see any one yard. A south-facing slope, a tree line, or a low frost pocket can shift a single site by half a zone either way, which is why neighboring gardeners often quote different numbers. We read the conditions at your exact address — soil, sun, slope, and frost — and score 1,112 plants against what's actually there.
Is the soil safe to grow vegetables in Nassau County?
The federal record around Nassau County is a meaningful one — 327 documented sites — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
Just moved to Nassau County — what should I know before planting?
Start with three facts. Nassau County sits in USDA zone 9a, which sets what survives winter; the statewide frost window runs about Jan 1 - Mar 15 to Nov 15 - never (south FL) (NOAA 30-year climate normals); and 327 documented sites sit on the federal record here, so a soil test before food beds is the smart first step. From there, matching plants to your actual soil and sun is the fun part.
Everything on this page is a Nassau County average. Your yard writes its own version — we read soil, sun, drainage, and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads Florida's frost window, season length, and soil profile against the plant's real requirements.