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

Planting zone for 00601 — Adjuntas, PR

ZIP code 00601 (Adjuntas, Adjuntas County) is in USDA zone 11b: the coldest winter night averages 45 to 50 °F.

Where ZIP 00601 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.

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

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 Adjuntas, PR…

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

Frost is rare or absent here: Adjuntas, PR is in zone 11b, where the coldest night of a typical winter stays above freezing. Cool-season vegetables grow best from fall through spring; summer heat, not frost, is the limit.

Native plants for zone 11b in Puerto Rico

145 plants native to Puerto Rico, recorded in Puerto Rico, and rated by the USDA to survive 45 °F or colder — the bottom of zone 11b. Each links to its USDA PLANTS profile.

Trees 36

Shrubs 46

Wildflowers & perennials 29

Grasses 33

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 Adjuntas, PR.

Soil in Adjuntas, PR

The soil mapped at the center of ZIP 00601 is Humatas — clay, well drained.

TextureClayholds water and nutrients; slow to drain and warm up
pH5.5moderately acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter7.5%high
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Humatas clay, 40 to 60 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 00601; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Adjuntas, PR

Longest day13 h 13 mindaylight on June 21
Shortest day11 h 02 mindaylight on December 21
Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb

Daylight is calculated from latitude.

Nearby ZIP codes

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

Puerto Rico planting zones →

Questions about 00601

What planting zone is ZIP code 00601?

ZIP code 00601 (Adjuntas, PR) 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).

What kind of soil does 00601 have?

The USDA soil survey maps Humatas at the center of ZIP 00601: clay, well drained, pH about 5.5 (moderately acidic).

What kind of onions grow in Adjuntas, PR?

Short-day onions: the longest day near 00601 is 13 h 13 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.