Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 33890 — Zolfo Springs, FL

ZIP code 33890 (Zolfo Springs, Hardee County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F.

Where ZIP 33890 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone9b25 to 30 °F

Coldest night−3.9 to −1.1 °C

Last frostrare

First frostrare

2012 zone9b

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 9b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Zolfo Springs, FL…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates

A 32 °F frost doesn't happen here in most winters. At the nearest station (NOAA station Wauchula, FL — 8 miles away, elevation 59 ft) the median growing season is 332 days. When frost does come, it is a midwinter night or two; cover tender plants when a freeze is forecast.

Frost data: NOAA NCEI U.S. Climate Normals 1991–2020.

When spring arrived in 2026

In 2026, spring leaf-out near 33890 came on Jan 12 — 3 days earlier than the 1991–2020 average (Jan 15).

average
Jan 152026
Jan 12

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 9b in Florida

477 plants native to the lower 48 states, recorded in Florida, and rated by the USDA to survive 25 °F or colder — the bottom of zone 9b. Each links to its USDA PLANTS profile.

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Zolfo Springs, FL.

Soil in Zolfo Springs, FL

The soil mapped at the center of ZIP 33890 is Wauchula — fine sand, poorly drained.

TextureFine sanddrains and warms fast; dries out and needs more feeding

pH4.6strongly acidic; most vegetables like 6.0–7.0

DrainagePoorly drainedconsider raised beds

Organic matter1.5%low — add compost

Hydrologic groupC/Dslow when drained; wet otherwise

Farmland classNot prime farmlandUSDA classification

Map unit: Wauchula fine sand.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 33890; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Zolfo Springs, FL

Summer high92 °Faverage high, July

Winter low48 °Faverage low, January

Hot days117days a year at 90 °F or more

Freezing nights5nights a year at 32 °F or less

Growing degree days8,218base 50 °F — the season’s usable heat

Longest day13 h 53 mindaylight on June 21

Shortest day10 h 24 mindaylight on December 21

Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb

Precipitation52 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Wauchula, FL (8 mi away); precipitation: Wauchula, FL (8 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9b.

Avon Park, FL · 17 mi

338349b

Bowling Green, FL · 17 mi

Florida planting zones →

Questions about 33890

What planting zone is ZIP code 33890?

ZIP code 33890 (Zolfo Springs, FL) is in USDA hardiness zone 9b on the 2023 map: the coldest night of an average winter reaches 25 to 30 °F (−3.9 to −1.1 °C).

How much rain and snow does 33890 get?

About 52 inches of precipitation a year (NOAA 1991–2020 normals, Wauchula station).

How hot do summers get in Zolfo Springs, FL?

The average high peaks at 92 °F in July, with about 117 days a year at 90 °F or more.

What kind of soil does 33890 have?

The USDA soil survey maps Wauchula at the center of ZIP 33890: fine sand, poorly drained, pH about 4.6 (strongly acidic).

Did spring come early in Zolfo Springs, FL in 2026?

Spring leaf-out near 33890 came on Jan 12 in 2026, 3 days earlier than the 1991–2020 average (Jan 15), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Zolfo Springs, FL?

Short-day onions: the longest day near 33890 is 13 h 53 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.