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

Planting zone for 33924 — Captiva, FL

ZIP code 33924 (Captiva, Lee County) is in USDA zone 11a: the coldest winter night averages 40 to 45 °F.

Where ZIP 33924 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.

Zone11a40 to 45 °F

Coldest night4.4 to 7.2 °C

Last frostrare

First frostrare

2012 zone10a

Was 10a on the 2012 map — a full zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 11a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Captiva, 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 Ft Myers Page Field Airport, FL — 20 miles away, elevation 16 ft) the median growing season is 365 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 33924 came on Jan 11 — about the same time as the 1991–2020 average (Jan 12).

average
Jan 122026
Jan 11

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 11a in Florida

518 plants native to the lower 48 states, recorded in Florida, and rated by the USDA to survive 40 °F or colder — the bottom of zone 11a. 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 Captiva, FL.

Soil in Captiva, FL

The soil mapped at the center of ZIP 33924 is Wulfert — muck, very poorly drained.

TextureMucktop layer

DrainageVery poorly drainedconsider raised beds

Organic matter75%high

Hydrologic groupA/Ddrains fast once dried out; wet otherwise

Farmland classNot prime farmlandUSDA classification

Map unit: Wulfert muck, tidal, 0 to 1 percent slopes.

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 33924; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Captiva, FL

Summer high92 °Faverage high, July

Winter low54 °Faverage low, January

Hot days120days a year at 90 °F or more

Freezing nights0nights a year at 32 °F or less

Growing degree days9,274base 50 °F — the season’s usable heat

Longest day13 h 48 mindaylight on June 21

Shortest day10 h 28 mindaylight on December 21

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

Precipitation54.8 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: Ft Myers Page Field Airport, FL (20 mi away); precipitation: Saint James City 0.4 Sse, FL (8 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

8 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

3395610b

Saint James City, FL · 4 mi

Cape Coral, FL · 11 mi

3399310b

Cape Coral, FL · 13 mi

3399110b

Cape Coral, FL · 13 mi

3390810b

Fort Myers, FL · 13 mi

Florida planting zones →

Questions about 33924

What planting zone is ZIP code 33924?

ZIP code 33924 (Captiva, FL) is in USDA hardiness zone 11a on the 2023 map: the coldest night of an average winter reaches 40 to 45 °F (4.4 to 7.2 °C).

How much rain and snow does 33924 get?

About 54.8 inches of precipitation a year (NOAA 1991–2020 normals, Saint James City 0.4 Sse station).

How hot do summers get in Captiva, FL?

The average high peaks at 92 °F in July, with about 120 days a year at 90 °F or more.

What kind of soil does 33924 have?

The USDA soil survey maps Wulfert at the center of ZIP 33924: muck, very poorly drained.

Did spring come early in Captiva, FL in 2026?

Spring leaf-out near 33924 came on Jan 11 in 2026, about the same as the 1991–2020 average (Jan 12), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Captiva, FL?

Short-day onions: the longest day near 33924 is 13 h 48 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.

Did the zone for 33924 change?

Yes. The 2012 USDA map put 33924 in zone 10a; the 2023 map puts it in zone 11a. The newer map uses 1991–2020 data and more weather stations.