The Treasure Coast spans USDA hardiness zone 10a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Florida's subtropical Atlantic shore — Indian River, St. Lucie, and Martin counties sit in USDA zone 10a with roughly 330 frost-free days, a long, near-frost-free season along the Indian River Lagoon that has long favored citrus and other warm-climate crops. A short list that earns its place here — mango, tomato, orange, and sweet potato — with any one site's soil, sun, and drainage making the final cut.
The Treasure Coast spans Florida.
Your yard isn't all of the Treasure Coast.
The Treasure Coast spans USDA zones 10a, but your parcel sits in exactly one — and slope, tree cover, and low spots nudge it further. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around Treasure Coast — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
The Treasure Coast — the short answer
The Treasure Coast: USDA zones 10a, 329–335 frost-free days, in Florida.
- USDA zones
- 10a
- USDA PHZM 2023, aggregated over the footprint
- Frost-free season
- 329–335 days
- NOAA Regional Climate Centers ACIS, 1991-2020
- Counties
- 3
- US Census TIGER/Line 2025
- Region type
- County cluster
- Growable Ground growing-region registry
Region boundary: Growable Ground growing-region registry — curated county clusters, EPA Level III ecoregions, and town clusters drawn finer than any county. Where a region publishes no measured season, no season figure is shown.
Hardiness Zone Range
What Grows in the Treasure Coast
Plants matched to the Treasure Coast's USDA zones 10a, ordered by how much hardiness margin each has across the region — the ones with room to spare at both ends of this band lead. Each links to its full growing profile.
Native Plants of the Treasure Coast
Plants the USDA PLANTS Database documents as native and present in this region’s state, kept only where the published hardiness range meets the Treasure Coast’s USDA zones 10a — closest range match first. Presence is recorded by state, so a plant can be documented across the state and still be scarce in your corner of the region.
The ground across the Treasure Coast
The USDA soil survey maps this ground county by county. These are those records weighted by land area across three member counties — this region’s own profile, not a state figure.
The ground is predominantly Spodosols, at 40% of mapped acres, followed by Alfisols (38%), Entisols (9%) and Histosols (7%). Six soil orders appear somewhere inside the footprint, which is the honest reason a regional soil answer only goes so far. The most extensive named soils are Riviera, Pineda, and Wabasso.
59% of those acres are poorly drained, and another 22% very poorly drained, 3% somewhat poorly drained. Topsoil pH runs 5.3–6.1 between the lowest and the highest county on record.
Soil order
Spodosols
Drainage
Poorly drained
Topsoil pH
5.3–6.1
Hydric soils
51%
Soil changes across a driveway, so which of these your own ground sits on is a parcel question rather than a regional one. Indian River County holds the most wetland ground here, at 62% — soil types explained.
USDA NRCS SSURGO via Soil Data Access
What this means for growing in the Treasure Coast
The soil survey reads this ground county by county, and the readings above are those records summed across the Treasure Coast. Here is what they mean for a garden here — and the move an experienced grower makes about each one.
Drainage
From county records59% of the mapped acres across the Treasure Coast are poorly drained — ground that sheds water slowly. That is area-weighted across all three of its mapped counties.
Beds can stay saturated for days after heavy rain, and the roots of most vegetables, berries, and fruit trees suffocate or rot in soil that never drains.
Raised beds or mounded rows lift roots above the wet zone; choose water-tolerant crops for the lowest spots.
USDA NRCS SSURGO
Surface pH
From county recordsTopsoil across the Treasure Coast runs pH 5.3–6.1 — acidic in all three of them.
Blueberries, potatoes, and rhododendrons thrive in it, but most vegetables start locking out nutrients below about pH 6.0 and grow pale and stunted no matter how much you feed them.
A measured lime application raises pH for the crops that need it — but test first, because the right rate depends on your own soil, not the county average.
USDA NRCS SSURGO
Safe to Grow Here?
What the federal record shows across the Treasure Coast — and how to grow with it.
Across the Treasure Coast's 3 counties the federal record holds 2,297 documented sites, mostly Underground Storage Tanks (1,210), Brownfields (724) and Nitrate (276). The heaviest single county is St. Lucie County, with 1,010.
That is a regional count, not a reading of any one lot — proximity to a documented site is information, not a diagnosis. Open the map outlined to the Treasure Coast to see which records sit where you actually grow.
Sources Checked
Summed across the 3 counties in the Treasure Coast
Know Before You Grow
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
Your land is one point inside the Treasure Coast
Everything above resolves to the Treasure Coast as a whole — a footprint spanning USDA zones 10a. Your parcel sits in exactly one of them. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at region scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better regional average.
Your Lot vs the Treasure Coast Average
Treasure Coast Average
- ●USDA Zones 10a, averaged across Treasure Coast
- ●One soil character for all of Treasure Coast
- ●State-average frost dates
YOUR Parcel
- ✓Your exact zone, not Treasure Coast's 10a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in the Treasure Coast
Pull a site-specific report for your exact address in the Treasure Coast — soil, sun, drainage, frost risk, contamination, and scored plant recommendations.
Three things about your lot that Treasure Coast averages can't show:
We read public map data around The Treasure Coast — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Treasure Coast average
How we know this about the Treasure Coast
The boundary: a cluster of neighboring counties. Growing regions have no official boundary, so this footprint is our published one, and every figure on this page was measured over the counties inside it rather than borrowed from the state around it.
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, aggregated across the footprint; the growing season from NOAA Regional Climate Centers ACIS 1991–2020 28°F normals, read at each member’s own record; boundaries from US Census TIGER/Line 2025; the contamination record from the federal sources named in that beat above; the soil from the USDA NRCS SSURGO survey, read at each member county’s own record and weighted to this footprint by land area. Where a member carries no record of its own, it is absent from the figure rather than filled in.
Common questions about the Treasure Coast
What hardiness zone is the Treasure Coast?
The Treasure Coast spans USDA hardiness zones 10a, aggregated from the USDA Agricultural Research Service Plant Hardiness Zone Map 2023 across the region's counties. Zones reflect average annual extreme minimum temperatures from 1991–2020 data.
How long is the growing season in the Treasure Coast?
Measured between 28°F hard freezes, the Treasure Coast's counties mostly run 330 to 333 frost-free days, median 330 (NOAA Regional Climate Centers ACIS, 1991–2020, over 3 member counties). That 3-day spread is the honest read — no single season describes 3 counties, and each county guide below carries its own.
When does frost risk end in the Treasure Coast?
Across the Treasure Coast, the middle half of member counties see their last 28°F hard freeze between Jan 19 and Jan 19 (median Jan 19), and their first fall freeze between Dec 15 and Dec 18. Those are hard freezes, not the last light frost: tender transplants wait for about Feb 9, and elevation decides which end of a 0-day spread you garden in.
What grows well in the Treasure Coast?
The Treasure Coast's conditions suit plants such as Mango, Tomato, Orange, Sweet Potato, Banana, Jalapeno. What actually thrives on any one site still turns on its specific soil, sun, and drainage — we score each plant against the real conditions at your address.
How is the Treasure Coast defined?
The Treasure Coast is defined here as a curated cluster of 3 neighboring counties that share a growing character. Growing regions have no official boundary, so this footprint is our published one — every county in it is named on this page.
Which states does the Treasure Coast cover?
The Treasure Coast spans Florida. Each state's full growing guide is linked on this page.
What other growing regions cover the same states?
Gulf Coast, Florida Panhandle, Northeast Florida, Southwest Florida (Naples–Fort Myers–Sarasota), Central Florida Ridge, and Everglades Agricultural Area share at least one state with the Treasure Coast. Growing regions overlap and interlock — a single address can sit inside more than one, which is why the precise read is always the parcel, not the region.
What this page reads at the Treasure Coast’s own scale
6 of the readings below were taken at the Treasure Coast's own scale — the zone 10a band across its footprint, a median 330-day season across its 3 counties and 2,297 documented federal contamination records across its 3 counties, 1,010 of them in St. Lucie County alone; one is borrowed from a wider read, named and linked below.
Measured here
- The USDA hardiness band 10a aggregated across all 3 counties in the footprintUSDA PHZM 2023
- The boundary itself — the 3 counties this region is curated fromGrowable Ground subregion registry
- The growing character that makes this region distinct from the states it crossesGrowable Ground subregion registry
- The 28°F season across the footprint — the middle half of its 3 counties run 330 to 333 frost-free days, median 330NOAA Regional Climate Centers ACIS, 1991-2020
- The federal contamination record over the whole footprint — 2,297 documented federal contamination records across its 3 counties, 1,010 of them in St. Lucie County aloneEPA, USGS and USDA federal site records
- The soil order mix across the footprint — 40% Spodosols, topsoil pH 5.3–6.1, area-weighted across its 3 mapped countiesUSDA NRCS SSURGO
Inherited from a wider read
- The candidate plant list — its state's curated sets, merged and filtered to zones 10afrom Florida
What this page can’t tell you
- Which end of the 3-day range your ground sits at — 330 days at one extreme, 333 at the other, decided mostly by elevationfrost dates explained →
- Which of those soils your own ground sits on — the survey maps them county-wide, and they change across a drivewaysoil types explained →
- The soil pH, drainage, sun hours, and frost pockets on one specific lotwhy one lot differs from the next →
Explore the Treasure Coast
State growing guides
Counties in this region
Other growing regions across Florida
The humid, near-frost-free coastal rim of the Gulf of Mexico — long seasons, sandy and alluvial soils, heat, and hurricanes shaping what thrives. (Representative coastal counties, not exhaustive.)
North Florida's mild-winter coastal plain of sandy and clay soils — a transition zone growing both Southern staples and subtropical fruit.
The Atlantic-facing northeast peninsula — Jacksonville, Gainesville, and St. Augustine along the St. Johns River — where ocean-moderated Zone 9a–9b winters and deep sandy coastal-plain flatwoods set a warmer floor and a tighter, earlier frost window than the Gulf-side Panhandle to the west (no genuine 8b interior here; last frost lands ~late January to mid-February).
Florida's lower Gulf coast — a near-frost-free subtropical corridor (USDA zone 10a–10b along the shore, dropping to 9b in the DeSoto interior) where mangrove shorelines, sandy and marl soils, and hurricane exposure shape what grows. Year-round warm-season vegetables and mainland tropical fruit thrive here on a Gulf-side footprint distinct from both the cooler Central Florida interior and the Atlantic shore at the same latitude.
The Lake Wales Ridge, a well-drained white-sand spine running about 100 miles down the Florida peninsula from Lake County south through Orange, Osceola, Polk, and Highlands, anchors this historic citrus belt in USDA zones 9b–10a with 323-to-335-day frost-free seasons.
The Everglades Agricultural Area is roughly 700,000 acres of drained peat-and-muck farmland south of Lake Okeechobee, defined under Florida's Everglades Forever Act (§373.4592, F.S.); its member counties span USDA zones 10a to 10b with a frost-free to 326-plus-day growing season, the deep organic soils behind the region's sugarcane and winter-vegetable harvests.