What to plant in September in Arizona
In Arizona (AZ), September is the heart of the growing season - about 26 weeks after the last frost (March 15) and 9 weeks before the first (November 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).
31 crops have a sowing or planting window this month, including bush bean, carrot, kale, radicchio, collard greens, endive & escarole - and 10 of those windows close during September.
Dates here come from Arizona frost dates (last frost Mar 15, first frost Nov 15). For one crop in detail, see when to plant bush bean, carrot or kale 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 September
Bush Bean (sow for a fall crop, by Sep 6) · Carrot (sow for a fall crop, by Sep 6) · Kale (sow for a fall crop, by Sep 6) · Radicchio (sow for a fall crop, by Sep 6) · Collard Greens (sow for a fall crop, by Sep 13) · Endive & Escarole (sow for a fall crop, by Sep 13) · Napa Cabbage (sow for a fall crop, by Sep 13) · Parsley (sow for a fall crop, by Sep 13) · Pea (sow for a fall crop, by Sep 13) · Swiss Chard (sow for a fall crop, by Sep 13)
For fall and winter harvests (29)
Sowings counted back from Arizona's first fall frost, so the crop matures before the cold - or, for garlic and similar, planted after it.
| Crop | What to do | Window | This month |
|---|---|---|---|
| Bush Bean | Sow for a fall crop | Aug 20 – Sep 6 | Last chance - ends Sep 6 |
| Carrot | Sow for a fall crop | Aug 20 – Sep 6 | Last chance - ends Sep 6 |
| Kale | Sow for a fall crop | Aug 20 – Sep 6 | Last chance - ends Sep 6 |
| Radicchio | Sow for a fall crop | Aug 20 – Sep 6 | Last chance - ends Sep 6 |
| Collard Greens | Sow for a fall crop | Aug 27 – Sep 13 | Last chance - ends Sep 13 |
| Endive & Escarole | Sow for a fall crop | Aug 27 – Sep 13 | Last chance - ends Sep 13 |
| Napa Cabbage | Sow for a fall crop | Aug 27 – Sep 13 | Last chance - ends Sep 13 |
| Parsley | Sow for a fall crop | Aug 27 – Sep 13 | Last chance - ends Sep 13 |
| Pea | Sow for a fall crop | Aug 27 – Sep 13 | Last chance - ends Sep 13 |
| Swiss Chard | Sow for a fall crop | Aug 27 – Sep 13 | Last chance - ends Sep 13 |
| Beet | Sow for a fall crop | Sep 3 – Sep 20 | Sep 3 – Sep 20 |
| Cilantro / Coriander | Sow for a fall crop | Sep 3 – Sep 20 | Sep 3 – Sep 20 |
| Bok Choy / Pak Choi | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Borage | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Dill | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Fava Bean (Broad Bean) | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Green Onion / Scallion | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Kohlrabi | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Lettuce | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Mache (Corn Salad) | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Mizuna | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Rapini (Broccoli Raab) | Sow for a fall crop | Sep 10 – Sep 27 | Sep 10 – Sep 27 |
| Chervil | Sow for a fall crop | Sep 17 – Oct 4 | Opens Sep 17 |
| Mustard Greens | Sow for a fall crop | Sep 17 – Oct 4 | Opens Sep 17 |
| Spinach | Sow for a fall crop | Sep 17 – Oct 4 | Opens Sep 17 |
| Tatsoi | Sow for a fall crop | Sep 17 – Oct 4 | Opens Sep 17 |
| Turnip | Sow for a fall crop | Sep 17 – Oct 4 | Opens Sep 17 |
| Arugula | Sow for a fall crop | Sep 24 – Oct 11 | Opens Sep 24 |
| Watercress | Sow for a fall crop | Sep 24 – Oct 11 | Opens Sep 24 |
Keep sowing (succession)
Repeat sowings of crops already in the ground, for a steady harvest instead of a glut.
- Zucchini / Summer Squash: sow again on Sep 6
- Basil: sow again on Sep 13
Harvesting in September
First harvests expected this month from crops sown or planted on time earlier in the season.
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.
Spring bulbs to plant in September in Arizona
Tulips, daffodils, hyacinths and crocus are planted in fall, once the soil has cooled and before it freezes. The exact window depends on the state, so our bulb guide quotes what each extension service says.
Peak growing season: September garden jobs in Arizona
- Water deeply two or three times a week rather than a little every day - about an inch a week, more in heat. See watering a vegetable garden.
- 9 weeks until the average first frost (November 15). Fall crops start now: bush bean, carrot, kale, radicchio. See the fall and winter garden guide.
- Check the undersides of leaves twice a week - catching pests early is most of the battle (pest identification guide).
- Harvest often: zucchini / summer squash should be coming in. Picking regularly keeps beans, squash and cucumbers producing.
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 September?
31 crops have a window in September: bush bean, carrot, kale, radicchio, collard greens, endive & escarole, napa cabbage, parsley, pea, swiss chard and more. The tables above give the exact dates for each.
Is it too late to plant garlic in Arizona in September?
Not too late - it's actually a little early. In Arizona the next garlic window opens around November 26: plant in fall, after first frost.
Is it too late to plant tomatoes in Arizona in September?
For this year, yes - the tomato windows in Arizona have closed. The next step is to start seeds indoors from about January 18.
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 can I harvest in Arizona in September?
From plantings made on time: zucchini / summer squash.
What to plant in September 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.