USDA zones 11b, 12a, 12b, 13a, 13b in PR
USDA plant hardiness zones 11b, 12a, 12b, 13a, 13b cover 7 locations across PR (average annual extreme minimum 45 to 60 °F): Adjuntas, PR, Culebra, PR, Culebra, PR, Ponce, PR, San Juan, PR, San Juan, PR, and 1 more. Average last spring frost across this state ranges March 13 (Culebra) to March 24 (Culebra), and growing seasons run 239–262 days (Culebra to Culebra) — even within one state, because hardiness sets winter survival, not planting dates. Here all 5 of its hardiness zones share this page rather than sit on 5 thin ones. The table below gives every PR location's own frost dates; the printable planting calendar uses Culebra, this state's median-season location.
- USDA zones
- 11b, 12a, 12b, 13a, 13b45 to 60 °F
- Last frost range
- Mar 13–Mar 24avg, 32°F
- First frost range
- Nov 17–Nov 30avg, 32°F
- Growing season range
- 239–262days
Locations in this group
Every location below keeps its own USDA zone, weather station, and frost dates — they are listed together here, not averaged. Find your town for its own numbers, or use the ZIP planner on the home page for an instant personalized answer.
| Location | Zone | Also covers | Nearest station | Last frost | First frost | Season (days) |
|---|---|---|---|---|---|---|
| Adjuntas | 11b | — | John Pennekamp Sp | frost-free | frost-free | 365 |
| Culebra * | 13a | Vieques | Sullivans Is | Mar 13 | Nov 30 | 262 |
| Culebra | 13b | — | Southport 5 N | Mar 24 | Nov 17 | 239 |
| Ponce | 12b | Bayamón, Mayagüez, Caguas, Hormigueros, Yauco, San Germán, +32 more | John Pennekamp Sp | frost-free | frost-free | 365 |
| San Juan | 13a | Ponce, Bayamón, Mayagüez, Carolina, Guaynabo, Fajardo, +33 more | John Pennekamp Sp | frost-free | frost-free | 365 |
| San Juan | 13b | Carolina, Cataño, Aguas Claras, Culebra, Caño Martin Peña | John Pennekamp Sp | frost-free | frost-free | 365 |
| Utuado | 12a | Barranquitas, Orocovis, Jayuya, Cayuco | John Pennekamp Sp | frost-free | frost-free | 365 |
* Culebra is this group's median-season location — the calendar below is computed from its data.
Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.
Planting calendar (Culebra, representative)
Computed from Culebra's average frost dates — the median-season location in this PRzones 11b, 12a, 12b, 13a, 13b group. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees — your own location's dates may run a week or two earlier or later (see the table above).
- Start indoors
- Plant out
- Fall sowing
- First harvest
| Crop | Frost tolerance | Start indoors | Plant out | First harvest | Fall planting | Season fit |
|---|---|---|---|---|---|---|
| Tomato | Tender | Jan 16 – Jan 30 | Mar 20 – Mar 27 | May 19 – Jun 8 | — | matures comfortably |
| Pepper | Very tender | Jan 2 – Jan 16 | Mar 27 – Apr 3 | May 26 – Jun 25 | — | matures comfortably |
| Cucumber | Tender | Feb 13 – Feb 20 | Mar 20 – Mar 27 | May 9 – May 29 | — | matures comfortably |
| Summer squash / zucchini | Tender | — | Mar 20 – Mar 27 | May 4 – May 19 | — | matures comfortably |
| Bush bean | Tender | — | Mar 20 – Mar 27 | May 9 – May 19 | Oct 1 – Oct 11 | matures comfortably |
| Sweet corn | Tender | — | Mar 13 – Mar 27 | May 12 – Jun 11 | — | matures comfortably |
| Basil | Very tender | Jan 30 – Feb 13 | Mar 20 – Mar 27 | Apr 19 – May 4 | — | matures comfortably |
| Lettuce | Half-hardy | Jan 30 – Feb 13 | Feb 13 – Feb 27 | Mar 30 – Apr 14 | Sep 17 – Oct 2 | matures comfortably |
| Pea | Hardy | — | Jan 30 – Feb 13 | Mar 26 – Apr 10 | Sep 7 – Sep 22 | matures comfortably |
| Spinach | Hardy | — | Jan 30 – Feb 13 | Mar 11 – Mar 21 | Sep 27 – Oct 7 | matures comfortably |
| Carrot | Half-hardy | — | Feb 20 – Feb 27 | Apr 21 – May 11 | Aug 28 – Sep 17 | matures comfortably |
| Broccoli | Half-hardy | Jan 16 – Jan 30 | Feb 13 – Feb 27 | Apr 9 – Apr 29 | Sep 2 – Sep 22 | matures comfortably |
Which crops fit this growing season
Using Culebra's own 262-day growing season (32°F, NOAA 1991–2020 median) against each crop's real days-to-maturity range: 12 of 12 crops mature here with comfortable margin. A different location in the table above with a longer or shorter season will get a different mix — the ZIP planner on the home page gives your own.
Frost & freeze dates (Culebra)
From NOAA's 1991–2020 Climate Normals at station USC00388405. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 — the conservative date to plant after or harvest before.
| Threshold | Last spring — avg | Last spring — 90%-safe | First fall — avg | First fall — 90%-safe | Season (days) |
|---|---|---|---|---|---|
| 36°F | Mar 25 | Apr 10 | Nov 16 | Dec 5 | 236 |
| 32°F (freeze) | Mar 13 | Mar 30 | Nov 30 | Dec 24 | 262 |
| 28°F | Mar 1 | Mar 22 | Dec 16 | Jan 10 | 288 |
| 24°F | Feb 9 | Mar 13 | Jan 2 | Jan 29 | 317 |
Growing degree days
Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. This group's median GDD (base 50°F) across all 7 locations is 10,139; Culebra's own reading is shown below.
| Model | °F·days | Used for |
|---|---|---|
| Base 50°F (warm-season) | 6,058 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 9,400 | cool-season crops (brassicas, greens) |
Hardiness zones 11b, 12a, 12b, 13a, 13b in PR
PR's 5 hardiness zones (11b, 12a, 12b, 13a, 13b) — an average annual extreme minimum winter temperature range of 45 to 60 °F on the USDA's 2023 map — share this page PR is small enough that every one of its hardiness zones (11b, 12a, 12b, 13a, 13b) is combined onto this one page rather than split thin across several. Each location's own zone is in the table above. Hardiness sets winter survival, not planting dates; the frost calendar uses Culebra, this page's representative location.
See all USDA hardiness zones across the site, or browse all PR locations.
Frequently asked questions
- What USDA hardiness zones does PR have?
- PR spans zones 11b, 12a, 12b, 13a, 13b — an average annual extreme minimum winter temperature range of 45 to 60 °F on the USDA's 2023 map — across 7 locations, each listed with its own zone in the table above. The zone does not set planting dates; see the frost calendar for that.
- Where in PR is the growing season longest?
- Culebra runs the longest season on this page at about 262 days; Culebra is shortest at about 239 days — hardiness zone is not what separates them, but they sit at different weather stations, so their frost calendars differ.
- When should I plant tomatoes in PR?
- Using Culebra's frost dates (this page's median-season location): start seeds indoors about Jan 16 – Jan 30, then transplant outside about Mar 20 – Mar 27. Your own location in the table above may differ by a week or two — use the ZIP planner on the home page for your exact station's dates.
- Does every location in PR have the same frost dates?
- No — they do not all share a weather station, so frost dates vary by a week or more across the 7 locations listed (see the table above for each location's own dates).
Sources & method
Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020, one reading per location's own nearest station (see the table above). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to each location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.