What to plant in January in Arizona
In Arizona (AZ), January sits about 8 weeks before the average last frost (March 15). The state averages 245 frost-free days a year (last frost March 15, first frost November 15; USDA zones 4b, 5b, 6b, 7b, 8b, 9b, 10b).
29 crops have a sowing or planting window this month - and 5 of those windows close during January.
Dates here come from Arizona frost dates (last frost Mar 15, first frost Nov 15). For one crop in detail, see when to plant onion, eggplant or bell pepper in Arizona.
Arizona covers a very wide range of climates, so dates near you can be two weeks or more either side of these. Enter your ZIP code in the planting calendar for dates tuned to your town.
Arizona: planting activity through the year
Last chance in January
Celeriac (start seeds indoors, by Jan 4) · Celery (start seeds indoors, by Jan 11) · Leek (start seeds indoors, by Jan 11) · Onion (start seeds indoors, by Jan 11) · Rosemary (start seeds indoors, by Jan 11)
Start seeds indoors in January (29)
Indoor sowings for transplants later. Six to eight weeks under lights is typical for tomatoes and peppers; onions and leeks need longer.
| Crop | What to do | Window | This month |
|---|---|---|---|
| Celeriac | Start seeds indoors | Dec 21 – Jan 4 | Last chance - ends Jan 4 |
| Celery | Start seeds indoors | Dec 28 – Jan 11 | Last chance - ends Jan 11 |
| Leek | Start seeds indoors | Dec 28 – Jan 11 | Last chance - ends Jan 11 |
| Onion | Start seeds indoors | Dec 28 – Jan 11 | Last chance - ends Jan 11 |
| Rosemary | Start seeds indoors | Dec 28 – Jan 11 | Last chance - ends Jan 11 |
| Eggplant | Start seeds indoors | Jan 4 – Jan 18 | Jan 4 – Jan 18 |
| Parsley | Start seeds indoors | Jan 4 – Jan 18 | Jan 4 – Jan 18 |
| Shallot | Start seeds indoors | Jan 4 – Jan 18 | Jan 4 – Jan 18 |
| Bell Pepper | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Chili Pepper | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Ginger | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Green Onion / Scallion | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Mint | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Oregano | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Sage | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Tarragon | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Thyme | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Turmeric | Start seeds indoors | Jan 11 – Jan 25 | Jan 11 – Jan 25 |
| Ground Cherry | Start seeds indoors | Jan 18 – Feb 1 | Opens Jan 18 |
| Lemon Balm | Start seeds indoors | Jan 18 – Feb 1 | Opens Jan 18 |
| Shiso (Perilla) | Start seeds indoors | Jan 18 – Feb 1 | Opens Jan 18 |
| Sweet Marjoram | Start seeds indoors | Jan 18 – Feb 1 | Opens Jan 18 |
| Tomatillo | Start seeds indoors | Jan 18 – Feb 1 | Opens Jan 18 |
| Tomato | Start seeds indoors | Jan 18 – Feb 1 | Opens Jan 18 |
| Broccoli | Start seeds indoors | Jan 25 – Feb 8 | Opens Jan 25 |
| Brussels Sprouts | Start seeds indoors | Jan 25 – Feb 8 | Opens Jan 25 |
| Cabbage | Start seeds indoors | Jan 25 – Feb 8 | Opens Jan 25 |
| Cauliflower | Start seeds indoors | Jan 25 – Feb 8 | Opens Jan 25 |
| Kale | Start seeds indoors | Jan 25 – Feb 8 | Opens Jan 25 |
Planting dates for popular crops in Arizona
Every crop has its own full-year dates for Arizona: indoor start, transplant or direct sowing, and harvest.
Seed-starting season: January garden jobs in Arizona
- Start 29 crops indoors this month, including celeriac, celery, leek, onion. Use a sterile mix and good light - see starting seeds indoors.
- 8 weeks until the average last frost (March 15). The seed-starting calculator works out each crop's exact sowing date from it.
- Keep seedlings from stretching: lights 2-3 inches above the leaves for 14-16 hours a day, and a fan or a daily brush of the hand across the tops.
- Prepare beds as soon as the soil crumbles instead of smearing when squeezed - working wet soil ruins its structure for the season.
USDA zone chart for Arizona
Arizona spans USDA zones 4b, 5b, 6b, 7b, 8b, 9b, 10b. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average.
Questions gardeners ask
What vegetables can I plant in Arizona in January?
29 crops have a window in January: celeriac, celery, leek, onion, rosemary, eggplant, parsley, shallot, bell pepper, chili pepper and more. The tables above give the exact dates for each.
Is it too late to plant tomatoes in Arizona in January?
No - start seeds indoors runs Jan 18 – Feb 1 in Arizona.
Is it too late to plant lettuce in Arizona in January?
Not too late - it's actually a little early. In Arizona the next lettuce window opens around February 8: start seeds indoors.
When is the first frost in Arizona?
The statewide average first fall frost is around November 15 and the last spring frost around March 15. Arizona covers a wide range of climates, so local dates can differ by two weeks or more - look yours up by ZIP code.
What should I start indoors in January in Arizona?
Celeriac (Dec 21 – Jan 4), Celery (Dec 28 – Jan 11), Leek (Dec 28 – Jan 11), Onion (Dec 28 – Jan 11), Rosemary (Dec 28 – Jan 11), Eggplant (Jan 4 – Jan 18), Parsley (Jan 4 – Jan 18), Shallot (Jan 4 – Jan 18), Bell Pepper (Jan 11 – Jan 25), Chili Pepper (Jan 11 – Jan 25), Ginger (Jan 11 – Jan 25), Green Onion / Scallion (Jan 11 – Jan 25), Mint (Jan 11 – Jan 25), Oregano (Jan 11 – Jan 25), Sage (Jan 11 – Jan 25), Tarragon (Jan 11 – Jan 25), Thyme (Jan 11 – Jan 25), Turmeric (Jan 11 – Jan 25), Ground Cherry (Jan 18 – Feb 1), Lemon Balm (Jan 18 – Feb 1), Shiso (Perilla) (Jan 18 – Feb 1), Sweet Marjoram (Jan 18 – Feb 1), Tomatillo (Jan 18 – Feb 1), Tomato (Jan 18 – Feb 1), Broccoli (Jan 25 – Feb 8), Brussels Sprouts (Jan 25 – Feb 8), Cabbage (Jan 25 – Feb 8), Cauliflower (Jan 25 – Feb 8), Kale (Jan 25 – Feb 8).
What to plant in January in other states
Dates are computed from Arizona’s statewide average frost dates (from NOAA/NCEI climate normals) and each crop’s timing in our crop database. Your garden may be a week or two either side - for dates tuned to your ZIP code, use the planting calendar.