Choose by type. Fast leafy brassicas such as bok choy, tatsoi, mizuna and komatsuna do best sown in fall and early spring. Heat-loving greens such as water spinach, amaranth and Malabar spinach carry the garden through midsummer. Napa cabbage is a fall-only crop. Alabama’s long season and hot, humid summers make that split work, and the sections below show where it bends.
The short answer for Alabama
The long growing season is what makes two plantings possible. At the reference airport station, the last spring freeze at 32°F falls between March 19 and April 3, and the first fall freeze between November 2 and November 16. Those dates mark the band where the chance of a 32°F freeze runs from 30 to 70 percent. They describe the airport, and suburban and rural gardens usually freeze later in spring and earlier in fall, often by one to two weeks, and more at elevation.
Winter is mild by national standards. At the Huntsville reference station, the mean daily minimum of the coldest month is 33.1°F. Nights hover right around freezing, so hardy greens often stand through the cold months with a row cover thrown over them on the hardest nights.
| Type | Examples | Best window | Why it fits |
|---|---|---|---|
| Quick leafy brassicas | Bok choy, tatsoi, mizuna, komatsuna | Early spring and fall | Baby leaves in about four weeks from sowing, before heat arrives |
| Asian mustards | Mustard greens, gai choy | Late winter and fall | Tolerate more warmth than bok choy, with a sharper flavor in heat |
| Heading types | Napa cabbage | Fall only | Needs cool weather the whole time it forms a head |
| Heat lovers | Water spinach, amaranth, Malabar spinach | After the soil warms, through summer | Thrive in heat but die at the first frost |
Which Asian greens handle Alabama summers?
Only the heat lovers. Water spinach grows fast in hot, wet weather and can be cut repeatedly. Amaranth, grown for its tender leaves, shrugs off July. Malabar spinach is a climbing vine that wants a trellis and a warm bed. All three are frost tender, so sow them after the last freeze window has passed for your area. For exact sowing dates by month, see When to Sow Asian Greens in Alabama. The broader overview is in Growing Asian Greens in Alabama.
What will not work here
Why does bok choy bolt in an Alabama spring?
Bok choy, tatsoi and napa cabbage respond to warming weather and lengthening days by sending up a flower stalk. Spring in Alabama warms quickly. A row sown in mid-April can go from seedling to flower stalk without ever making a decent head, because the weather turns hot before the plants fill out. Early spring sowing, as soon as the soil can be worked, gives the leaves a few cool weeks. After that, switch to the heat lovers.
Napa cabbage fails in the same way, only more expensively. It needs weeks of cool weather to fold into a head, and a spring sowing rarely gets them. Sow it in fall so the head forms as nights cool, and plan on a freeze cover when the first hard frost arrives.
Does close spacing cause problems in humid summers?
Yes. Alabama’s humidity keeps leaves wet long after rain or dew, and crowded brassicas hold that moisture against the foliage. That invites downy mildew, black rot and soft rot at the base of the head. Give bok choy and mustards the full spacing on the seed packet, and water the soil at the base in the morning rather than overhead in the evening.
Once-a-week watering fails too. Alabama rain tends to arrive in heavy bursts, and red clay soils shed much of it before it soaks in, then dry into a crust. Shallow-rooted greens need steady moisture, so mulch the bed and check the soil with a finger rather than the calendar.
Sowing too late in fall is the other common loss. Seedlings started in late October grow slowly as days shorten and may be small when hard freezes arrive. Pests also limit what survives: flea beetles pit spring leaves, and cabbage loopers and harlequin bugs feed on fall crops. A light row cover over the whole bed, tucked in at the edges, handles most of them.
What changes across Alabama
Alabama is not one garden. On the USDA Plant Hardiness Zone Map 2023, the state runs from zone 7a to 9a, which is three zones of spread, so no single recommendation covers it. That map is built on one variable, the average annual extreme minimum temperature. It tells you what winter cold a plant must survive, and nothing about summer heat or the date of the last freeze.
In the north, including the Tennessee Valley and higher ground in the hills, spring comes later and fall frost arrives sooner. The window for spring bok choy is shorter. Fall sowing should start earlier, in late summer, so plants have size before cold arrives. Elevation adds to this. A garden on a ridge can freeze one to two weeks past the airport dates in spring and ahead of them in fall. Fall greens there should go under row cover earlier.
Toward the Gulf Coast, the picture reverses. Winters are mild enough that tatsoi, mizuna and mustards can keep producing for most of the cool season. Spring heat also arrives sooner, so the cool-season window closes earlier and the shift to water spinach and amaranth should come earlier. Central Alabama sits between the two, with heavy clay in places that demands raised beds or added compost to drain well.
To find your own zone, look up your location on the USDA Plant Hardiness Zone Map rather than guessing from a neighbor’s garden. Then use the zone for winter survival and your county’s frost dates for sowing.
Where to check this for your own county
The Alabama Cooperative Extension System is the place to confirm everything above. It is the state’s land-grant extension service, and it has offices that serve each county.
Look for two things. The first is a local planting calendar for leafy greens and brassicas, with sowing windows adjusted to your area’s frost dates. The second is any record of varieties trialled in your county or one nearby. A variety that holds up in the Tennessee Valley may bolt on the Gulf Coast, and trial results show which ones stood up to local heat, humidity and disease.
County extension agents can also explain how to take a soil sample and read the results. Alabama’s clay soils vary a lot, and a soil test tells you whether to lime, how much to feed, and whether drainage is the problem before you blame the seed.
A county recommendation beats a statewide one every time, including the ranges given here. Treat the state-level guidance as a starting point, and let the county office’s numbers decide your first sowing date. If the local advice differs from a general rule, trust the local advice.
Checking this against your own garden
Your own observations outrank every date in a guide. Three are worth tracking.
- Soil warmth by feel. Push your hand two inches into the bed in the morning. If it feels cold and clammy, brassica seed will sit. Beds that warm first, such as raised or south-facing ones, can be sown days or weeks ahead of shaded or low clay beds.
- First true leaves. The first pair after the seed leaves shows how fast seedlings are moving. Weeks of stalling point to cold soil, shade or crusted clay. Rapid growth means you can sow the next row sooner.
- First flower stalk. When the center of a bok choy or mustard plant starts to lengthen, the bed has reached its heat limit. Note the date, and next year sow so harvest finishes before it.
Keep a few lines in a notebook each season. Cold air also pools in low spots, so a bed at the bottom of a slope may freeze while the top of the yard stays clear, and a year or two of notes will show it.
Common questions
Is bok choy easier than napa cabbage in Alabama?
Yes. Bok choy matures faster and gives you usable leaves along the way. Napa cabbage needs a long stretch of cool weather to form a head, so it works only as a fall crop.
Can Asian greens grow through an Alabama winter?
Often, yes. The coldest month’s mean daily minimum is 33.1°F at the Huntsville reference station, so hardy types like tatsoi, mizuna and mustards commonly survive with a row cover on the hardest nights. Gardens in the northern part of the state face deeper cold than the Gulf Coast.
What can I grow in July and August?
Water spinach, amaranth and Malabar spinach. Bok choy and napa cabbage will bolt or sulk in that heat, so wait until late summer or fall to sow them.
How often should I sow Asian greens?
Sow small batches every two weeks within each window rather than one big planting. Most leafy types go from baby leaf to bolting quickly, and staggered rows keep a steady harvest coming.