Del Rio, TX planting zone & frost dates
Del Rio is in USDA hardiness zone 9a. The last spring frost usually comes around February 16 and the first fall frost around December 3, for a growing season of about 293 days.
Planting calendar for Del Rio
Dates are counted from the average last spring frost (February 16) 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 22 – Jan 5 Transplant outdoors: Feb 23 – Mar 2 |
| Peppers | Start seeds indoors: Dec 8 – Dec 22 Transplant outdoors: Mar 2 – Mar 9 |
| Eggplant | Start seeds indoors: Dec 8 – Dec 22 Transplant outdoors: Mar 2 – Mar 9 |
| Broccoli | Start seeds indoors: Dec 8 – Dec 22 Transplant outdoors: Jan 19 – Feb 2 |
| Cabbage | Start seeds indoors: Dec 8 – Dec 22 Transplant outdoors: Jan 19 – Feb 2 |
| Onions (sets) | Plant outdoors: Jan 19 – Feb 2 |
| Peas | Sow outdoors: Jan 5 – Jan 19 |
| Spinach | Sow outdoors: Jan 5 – Jan 19 |
| Lettuce | Sow outdoors: Jan 19 – Feb 2 |
| Carrots | Sow outdoors: Jan 19 – Feb 2 |
| Potatoes | Plant outdoors: Jan 19 – Feb 2 |
| Beans | Sow outdoors: Feb 23 – Mar 2 |
| Sweet corn | Sow outdoors: Feb 23 – Mar 2 |
| Cucumbers | Sow outdoors: Feb 23 – Mar 2 |
| Squash & zucchini | Sow outdoors: Feb 23 – Mar 2 |
| Basil | Start seeds indoors: Jan 5 – Jan 19 Transplant outdoors: Feb 23 – Mar 2 |
Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Oct 8 (8 weeks before the average first fall frost on Dec 3).
Useful for zone 9a 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
As an Amazon Associate, FrostZoneMap earns from qualifying purchases, at no extra cost to you.
Frost risk in detail
| 90% chance | 50% chance | 10% chance | |
|---|---|---|---|
| Last 32°F frost in spring is after | Jan 19 | Feb 16 | Mar 10 |
| First 32°F frost in fall is before | Dec 26 | Dec 3 | Nov 14 |
How to read it: in spring there is a 10% chance of a frost after March 10, so that is a safe date for tender plants. In fall there is a 10% chance of frost before November 14. A hard freeze (28°F) usually ends around January 24.
Hardiness zone by ZIP code in Del Rio
- 78840 zone 8b
- 78841 zone 8b
- 78842 zone 9a
- 78847 zone 9a
Nearby cities
- Eagle Pass zone 9a, last frost Feb 19
- Uvalde zone 9a
- Kerrville zone 8b, last frost Mar 27
- San Angelo zone 8a, last frost Mar 20
- Boerne zone 8b, last frost Mar 15
- Fredericksburg zone 8b, last frost Mar 18
- Laredo zone 9b, last frost Jan 20
- San Antonio zone 9a, last frost Feb 25
Questions
What growing zone is Del Rio, TX?
Del Rio is in USDA Plant Hardiness Zone 9a (average extreme winter low 20°F to 25°F), according to the USDA 2023 map. Some ZIP codes of the city fall in zone 8b.
When is the last frost in Del Rio?
The average last spring frost (32°F) in Del Rio is February 16. There is still a 10% chance of frost until March 10.
When can I plant tomatoes in Del Rio?
Transplant tomatoes outdoors 1–2 weeks after the average last frost: around Feb 23 – Mar 2. Start seeds indoors 6–8 weeks before the last frost.
Frost dates: NOAA U.S. Climate Normals 1991–2020, station Del Rio Intl Ap, TX (USW00022010), 3.4 km (2.1 mi) from the city center, elevation 304 m, based on 26 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.