Mesa, AZ planting zone & frost dates
Mesa is in USDA hardiness zone 9b. The last spring frost usually comes around February 13 and the first fall frost around December 5, for a growing season of about 298 days.
Planting calendar for Mesa
Dates are counted from the average last spring frost (February 13) 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 19 – Jan 2 Transplant outdoors: Feb 20 – Feb 27 |
| Peppers | Start seeds indoors: Dec 5 – Dec 19 Transplant outdoors: Feb 27 – Mar 6 |
| Eggplant | Start seeds indoors: Dec 5 – Dec 19 Transplant outdoors: Feb 27 – Mar 6 |
| Broccoli | Start seeds indoors: Dec 5 – Dec 19 Transplant outdoors: Jan 16 – Jan 30 |
| Cabbage | Start seeds indoors: Dec 5 – Dec 19 Transplant outdoors: Jan 16 – Jan 30 |
| Onions (sets) | Plant outdoors: Jan 16 – Jan 30 |
| Peas | Sow outdoors: Jan 2 – Jan 16 |
| Spinach | Sow outdoors: Jan 2 – Jan 16 |
| Lettuce | Sow outdoors: Jan 16 – Jan 30 |
| Carrots | Sow outdoors: Jan 16 – Jan 30 |
| Potatoes | Plant outdoors: Jan 16 – Jan 30 |
| Beans | Sow outdoors: Feb 20 – Feb 27 |
| Sweet corn | Sow outdoors: Feb 20 – Feb 27 |
| Cucumbers | Sow outdoors: Feb 20 – Feb 27 |
| Squash & zucchini | Sow outdoors: Feb 20 – Feb 27 |
| Basil | Start seeds indoors: Jan 2 – Jan 16 Transplant outdoors: Feb 20 – Feb 27 |
Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Oct 10 (8 weeks before the average first fall frost on Dec 5).
Useful for zone 9b 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 12 | Feb 13 | Mar 9 |
| First 32°F frost in fall is before | Dec 24 | Dec 5 | Nov 18 |
How to read it: in spring there is a 10% chance of a frost after March 9, so that is a safe date for tender plants. In fall there is a 10% chance of frost before November 18. A hard freeze (28°F) usually ends around January 16.
Hardiness zone by ZIP code in Mesa
- 85201 zone 9b
- 85202 zone 10a
- 85203 zone 9b
- 85204 zone 9b
- 85205 zone 9b
- 85206 zone 9b
- 85207 zone 9b
- 85208 zone 9b
- 85209 zone 9b
- 85210 zone 10a
- 85211 zone 10a
- 85212 zone 9b
- 85213 zone 9b
- 85214 zone 9b
- 85215 zone 9b
- 85216 zone 9b
- 85274 zone 10a
- 85275 zone 9b
- 85277 zone 9b
Nearby cities
- Gilbert zone 9b, last frost Feb 13
- Tempe zone 10a, last frost Feb 13
- Scottsdale zone 10a, last frost Feb 13
- Chandler zone 9b, last frost Feb 13
- Tempe Junction zone 9b, last frost Feb 13
- Paradise Valley zone 10a, last frost Jan 6
- Fountain Hills zone 9b, last frost Jan 6
- Sun Lakes zone 9b, last frost Feb 1
Questions
What growing zone is Mesa, AZ?
Mesa is in USDA Plant Hardiness Zone 9b (average extreme winter low 25°F to 30°F), according to the USDA 2023 map. Some ZIP codes of the city fall in zone 10a.
When is the last frost in Mesa?
The average last spring frost (32°F) in Mesa is February 13. There is still a 10% chance of frost until March 9.
When can I plant tomatoes in Mesa?
Transplant tomatoes outdoors 1–2 weeks after the average last frost: around Feb 20 – Feb 27. Start seeds indoors 6–8 weeks before the last frost.
Frost dates: NOAA U.S. Climate Normals 1991–2020, station Tempe Asu, AZ (USC00028499), 9.2 km (5.7 mi) from the city center, elevation 356 m, based on 24 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.