Sulphur, LA planting zone & frost dates
Sulphur is in USDA hardiness zone 9a. The last spring frost usually comes around March 2 and the first fall frost around November 25, for a growing season of about 267 days.
Planting calendar for Sulphur
Dates are counted from the average last spring frost (March 2) 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: Jan 5 – Jan 19 Transplant outdoors: Mar 9 – Mar 16 |
| Peppers | Start seeds indoors: Dec 22 – Jan 5 Transplant outdoors: Mar 16 – Mar 23 |
| Eggplant | Start seeds indoors: Dec 22 – Jan 5 Transplant outdoors: Mar 16 – Mar 23 |
| Broccoli | Start seeds indoors: Dec 22 – Jan 5 Transplant outdoors: Feb 2 – Feb 16 |
| Cabbage | Start seeds indoors: Dec 22 – Jan 5 Transplant outdoors: Feb 2 – Feb 16 |
| Onions (sets) | Plant outdoors: Feb 2 – Feb 16 |
| Peas | Sow outdoors: Jan 19 – Feb 2 |
| Spinach | Sow outdoors: Jan 19 – Feb 2 |
| Lettuce | Sow outdoors: Feb 2 – Feb 16 |
| Carrots | Sow outdoors: Feb 2 – Feb 16 |
| Potatoes | Plant outdoors: Feb 2 – Feb 16 |
| Beans | Sow outdoors: Mar 9 – Mar 16 |
| Sweet corn | Sow outdoors: Mar 9 – Mar 16 |
| Cucumbers | Sow outdoors: Mar 9 – Mar 16 |
| Squash & zucchini | Sow outdoors: Mar 9 – Mar 16 |
| Basil | Start seeds indoors: Jan 19 – Feb 2 Transplant outdoors: Mar 9 – Mar 16 |
Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Sep 30 (8 weeks before the average first fall frost on Nov 25).
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 30 | Mar 2 | Mar 26 |
| First 32°F frost in fall is before | Dec 21 | Nov 25 | Nov 3 |
How to read it: in spring there is a 10% chance of a frost after March 26, so that is a safe date for tender plants. In fall there is a 10% chance of frost before November 3. A hard freeze (28°F) usually ends around February 11.
Hardiness zone by ZIP code in Sulphur
- 70663 zone 9a
- 70664 zone 9a
- 70665 zone 9b
Nearby cities
- Lake Charles zone 9a, last frost Feb 14
- Moss Bluff zone 9a, last frost Mar 2
- DeRidder zone 9a, last frost Mar 1
- Jennings zone 9a, last frost Feb 19
- Eunice zone 9a, last frost Feb 26
- Crowley zone 9a, last frost Feb 20
- Abbeville zone 9a, last frost Feb 17
- Opelousas zone 9a, last frost Feb 28
Questions
What growing zone is Sulphur, LA?
Sulphur 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 9b.
When is the last frost in Sulphur?
The average last spring frost (32°F) in Sulphur is March 2. There is still a 10% chance of frost until March 26.
When can I plant tomatoes in Sulphur?
Transplant tomatoes outdoors 1–2 weeks after the average last frost: around Mar 9 – Mar 16. Start seeds indoors 6–8 weeks before the last frost.
Frost dates: NOAA U.S. Climate Normals 1991–2020, station Moss Bluff 2 Nnw, LA (USC00166434), 19.3 km (12.0 mi) from the city center, elevation 8 m, based on 11 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.