Portland, TX planting zone & frost dates
Portland is in USDA hardiness zone 10a. The last spring frost usually comes around January 31 and the first fall frost around December 22, for a growing season of about 331 days.
Planting calendar for Portland
Dates are counted from the average last spring frost (January 31) using the typical timing recommended by U.S. extension services. Warm-season crops go out only after the danger of frost has passed and the soil has warmed.
| Crop | When |
|---|---|
| Tomatoes | Start seeds indoors: Dec 6 – Dec 20 Transplant outdoors: Feb 7 – Feb 14 |
| Peppers | Start seeds indoors: Nov 22 – Dec 6 Transplant outdoors: Feb 14 – Feb 21 |
| Eggplant | Start seeds indoors: Nov 22 – Dec 6 Transplant outdoors: Feb 14 – Feb 21 |
| Broccoli | Start seeds indoors: Nov 22 – Dec 6 Transplant outdoors: Jan 3 – Jan 17 |
| Cabbage | Start seeds indoors: Nov 22 – Dec 6 Transplant outdoors: Jan 3 – Jan 17 |
| Onions (sets) | Plant outdoors: Jan 3 – Jan 17 |
| Peas | Sow outdoors: Dec 20 – Jan 3 |
| Spinach | Sow outdoors: Dec 20 – Jan 3 |
| Lettuce | Sow outdoors: Jan 3 – Jan 17 |
| Carrots | Sow outdoors: Jan 3 – Jan 17 |
| Potatoes | Plant outdoors: Jan 3 – Jan 17 |
| Beans | Sow outdoors: Feb 7 – Feb 14 |
| Sweet corn | Sow outdoors: Feb 7 – Feb 14 |
| Cucumbers | Sow outdoors: Feb 7 – Feb 14 |
| Squash & zucchini | Sow outdoors: Feb 7 – Feb 14 |
| Basil | Start seeds indoors: Dec 20 – Jan 3 Transplant outdoors: Feb 7 – Feb 14 |
Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Oct 27 (8 weeks before the average first fall frost on Dec 22).
Useful for zone 10a gardens
- Seed starting kit with dome — to start seeds indoors before the last frost
- LED grow light for seedlings — stops leggy seedlings
- Frost cloth / plant covers — for late spring and early fall frosts
- Soil thermometer — warm-season crops need soil above 60°F
- Shade cloth — for hot summers
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Frost risk in detail
| 90% chance | 50% chance | 10% chance | |
|---|---|---|---|
| Last 32°F frost in spring is after | Dec 24 | Jan 31 | Mar 2 |
| First 32°F frost in fall is before | Feb 1 | Dec 22 | Nov 29 |
How to read it: in spring there is a 10% chance of a frost after March 2, so that is a safe date for tender plants. In fall there is a 10% chance of frost before November 29. A hard freeze (28°F) usually ends around January 11.
Hardiness zone by ZIP code in Portland
- 78374 zone 10a
Nearby cities
- Corpus Christi zone 10a, last frost Jan 31
- Rockport zone 9b, last frost Jan 31
- Robstown zone 9b, last frost Jan 26
- Kingsville zone 9b, last frost Jan 25
- Beeville zone 9b, last frost Feb 17
- Alice zone 9b, last frost Jan 29
- Victoria zone 9b, last frost Feb 14
- Port Lavaca zone 9b, last frost Feb 1
Questions
What growing zone is Portland, TX?
Portland is in USDA Plant Hardiness Zone 10a (average extreme winter low 30°F to 35°F), according to the USDA 2023 map.
When is the last frost in Portland?
The average last spring frost (32°F) in Portland is January 31. There is still a 10% chance of frost until March 2.
When can I plant tomatoes in Portland?
Transplant tomatoes outdoors 1–2 weeks after the average last frost: around Feb 7 – Feb 14. Start seeds indoors 6–8 weeks before the last frost.
Frost dates: NOAA U.S. Climate Normals 1991–2020, station Corpus Christi Nws, TX (USC00412011), 20.9 km (13.0 mi) from the city center, elevation 13 m, based on 13 years of records. Hardiness zone: USDA Plant Hardiness Zone Map 2023 for the ZIP code nearest to the city center. Microclimates (valleys, hills, cities, coasts) can be warmer or colder: check the local forecast before planting. How we calculate the data.