When to Plant Turnips in Arizona
Published: April 24, 2026
Arizona gardeners in Zone 9b enjoy an extended 50-week growing season for turnip. Cool-season crops like turnip do best in fall, winter, and early spring in Arizona — the hot summers bolt these plants before they can be harvested. This guide gives exact dates for Arizona based on your local frost calendar.
Turnip Planting Dates for Arizona
| Start seeds indoors | Year-round |
| Last frost (average) | January 15 |
| Direct sow outdoors | December 25–January 4 |
| Expect first harvest | January 29 – February 23 |
| Fall crop start | November 5–15 |
| Fall harvest | December 10 |
| First fall frost (average) | December 31 |
Dates above assume Zone 9b, the most common zone in Arizona. Gardeners in cooler San Tan Valley (Zone 7b) plant 1–2 weeks later; warmer Tucson (Zone 9a) can plant 1–2 weeks earlier.
⚠ Direct sow turnips 2–4 weeks before last frost for spring crop. Best planted in late summer (6–8 weeks before first fall frost) for fall harvest — frost sweetens the roots. Fast-growing: some varieties ready in just 35 days.
Growing Turnips in Arizona's Climate
Arizona's warm Zone 9b climate makes turnip a fall, winter, and early spring crop rather than a summer one. The cool-season window runs roughly October through April in Arizona — plant outside this window and the turnip will bolt (send up a flower stalk and turn bitter) before it produces a harvestable crop.
Succession planting stretches the turnip harvest window. Sow small amounts every two weeks from October through February — you will have staggered harvests rather than a single wave to process all at once. Bolt-resistant varieties extend the usable window an extra three to four weeks into warming weather.
Common turnip pests to watch for in Arizona include Flea Beetle and Aphid. The first line of defense is companion planting: Pea and Mint planted nearby discourage several of these pests by confusing host-plant identification or repelling adults before they can lay eggs. Weekly garden walks in the early morning catch problems when they're still manageable.
Turnip Garden Calendar for Arizona
| Month | Task | Notes |
|---|---|---|
| January | First harvest window opens | Turnip begins producing 35–60 days after transplant |
| February | — | Off-season |
| March | — | Off-season |
| April | — | Off-season |
| May ← | Watch for bolting | Harvest promptly; spring heat arrives quickly |
| June | — | Off-season |
| July | — | Off-season |
| August | — | Off-season |
| September | — | Off-season |
| October | — | Off-season |
| November | Fall crop planting | Transplant or direct sow for fall harvest before frost |
| December | Direct sow seeds | Sow seeds 1/4–1/2 inch deep, 4 inches apart |
Turnip Growing Tips for Arizona Gardeners
- •Thin seedlings to 4-inch spacing when plants are 3 inches tall — crowded turnips produce small woody roots.
- •Both roots AND greens are edible — harvest baby turnip greens 4 weeks after sowing, roots 5–9 weeks.
- •Arizona's cool-season turnip plants best in October, November, and December for winter and early spring harvest. Spring plantings bolt before producing a harvestable crop.
- •Fall turnips are sweetest — plant 8 weeks before first frost and let cold weather convert starches to sugars.
Companion Planting for Turnips in Arizona
In Arizona's warm climate, planting turnip with Pea and Mint helps deter pests and improve soil. Avoid planting near Potato and Radish, which inhibit turnip growth through root chemistry or shared pest pressure. See the full turnip companion planting guide for the complete list.
Turnips Planting Dates by City in Arizona
Top cities in Arizona — select for city-level frost dates and planting calendars.
Frequently Asked Questions
When should I plant turnip in Arizona?
In Arizona (Zone 9b), start turnip seeds indoors around Year-round and transplant outdoors around null — 0 weeks after the state's average last frost of January 15.
What is the last frost date in Arizona?
Arizona's average last frost date is January 15 in the state's most common Zone 9b. Frost dates vary by city — higher elevations and northern counties run 1 to 3 weeks later than the state average. See the city list below for city-level frost dates.
Can I grow turnip year-round in Arizona?
turnip is a cool-season crop in Arizona, with spring and fall windows. Summer heat bolts the plants before they can produce a harvestable crop. Succession planting every 2–3 weeks stretches the harvest window.
What turnip varieties grow best in Arizona?
For Arizona's Zone 9b, consult a local nursery or extension office for turnips variety recommendations.
When do I start turnip seeds indoors in Arizona?
Turnip does not need indoor starting in Arizona — direct sow around December 25–January 4 once soil reaches 40°F. Indoor starting is not recommended for this crop because turnip transplants poorly.