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

Planting zone for 33045 — Key West, FL

ZIP code 33045 (Key West, Monroe County) is in USDA zone 11b: the coldest winter night averages 45 to 50 °F.

Where ZIP 33045 is

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.

Zone11b45 to 50 °F
Coldest night7.2 to 10 °C
Last frostrare
First frostrare
2012 zone11b

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 11b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Key West, 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 Everglades, FL — 93 miles away, elevation 7 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 33045 came on Jan 9 — about the same time as the 1991–2020 average (Jan 9).

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 11b in Florida

521 plants native to the lower 48 states, recorded in Florida, and rated by the USDA to survive 45 °F or colder — the bottom of zone 11b. Each links to its USDA PLANTS profile.

Trees 72

Shrubs 134

Wildflowers & perennials 154

Grasses 141

Vines 12

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 Key West, FL.

Soil in Key West, FL

The soil mapped at the center of ZIP 33045 is Pennekamp — gravelly muck, moderately well drained. Much of the area is built over (urban land); this is the natural soil underneath.

TextureGravelly mucktop layer
DrainageModerately well drainednatural drainage class
Organic matter75%high
Hydrologic groupB/Dmoderate when drained; wet otherwise
Farmland classNot prime farmlandUSDA classification

Map unit: Urban land, 0 to 2 percent slopes, frequently flooded.

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 33045; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Key West, FL

Summer high90 °Faverage high, July
Winter low63 °Faverage low, January
Hot days54days a year at 90 °F or more
Freezing nights0nights a year at 32 °F or less
Growing degree days9,993base 50 °F — the season’s usable heat
Longest day13 h 40 mindaylight on June 21
Shortest day10 h 37 mindaylight on December 21
Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb
Precipitation46.5 inper year, rain and melted snow

Average high and low, by month

50°60°70°80°90°100°January: average high 75 °F, low 63 °F 75°63° JanFebruary: average high 77 °F, low 64 °F 77°64° FebMarch: average high 79 °F, low 67 °F 79°67° MarApril: average high 83 °F, low 71 °F 83°71° AprMay: average high 86 °F, low 74 °F 86°74° MayJune: average high 88 °F, low 77 °F 88°77° JunJuly: average high 90 °F, low 78 °F 90°78° JulAugust: average high 90 °F, low 79 °F 90°79° AugSeptember: average high 88 °F, low 77 °F 88°77° SepOctober: average high 85 °F, low 75 °F 85°75° OctNovember: average high 81 °F, low 70 °F 81°70° NovDecember: average high 77 °F, low 66 °F 77°66° Dec

Precipitation by month inches

0″2″4″6″8″January: 1.85 in precipitation 1.9 JanFebruary: 1.89 in precipitation 1.9 FebMarch: 1.62 in precipitation 1.6 MarApril: 2.37 in precipitation 2.4 AprMay: 3.95 in precipitation 4.0 MayJune: 5.33 in precipitation 5.3 JunJuly: 5.31 in precipitation 5.3 JulAugust: 6.20 in precipitation 6.2 AugSeptember: 8.01 in precipitation 8.0 SepOctober: 5.32 in precipitation 5.3 OctNovember: 2.48 in precipitation 2.5 NovDecember: 2.16 in precipitation 2.2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Key W WFO, FL (within 1 mile); precipitation: Key West 0.5 Sw, FL (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 11b.

All 3 ZIP codes in Key West → · Florida planting zones →

Questions about 33045

What planting zone is ZIP code 33045?

ZIP code 33045 (Key West, FL) is in USDA hardiness zone 11b on the 2023 map: the coldest night of an average winter reaches 45 to 50 °F (7.2 to 10 °C).

How much rain and snow does 33045 get?

About 46.5 inches of precipitation a year (NOAA 1991–2020 normals, Key West 0.5 Sw station).

How hot do summers get in Key West, FL?

The average high peaks at 90 °F in July, with about 54 days a year at 90 °F or more.

What kind of soil does 33045 have?

The USDA soil survey maps Pennekamp at the center of ZIP 33045: gravelly muck, moderately well drained.

Did spring come early in Key West, FL in 2026?

Spring leaf-out near 33045 came on Jan 9 in 2026, about the same as the 1991–2020 average (Jan 9), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Key West, FL?

Short-day onions: the longest day near 33045 is 13 h 40 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.