In south Louisiana, sow Asian greens from early fall through winter and into late winter, then stop before summer heat arrives. The sowing calendar here is set by heat rather than frost, and the numbers below come from the New Orleans reference station. Treat them as a starting frame for a state with a very wide climate spread.
The short answer for Louisiana
The frost numbers look strange to anyone used to a northern calendar. At the reference station, the NOAA 1991-2020 Climate Normals put the last spring frost between January 18 and February 8, and the first fall frost between December 17 and January 8. Those are probabilities of a 32°F freeze, taken from the 30 to 70 percent band. They are not promises. In a given year the freeze can come before that window or after it.
The bigger surprise is how often the freeze never comes. A 32°F freeze occurs in only 86.8 percent of years at this station, which means roughly one year in seven has no freeze at all. The fall window straddles the New Year, so “first fall frost” and “last spring frost” are only about a month apart. A calendar built around them would leave you with almost nothing to plant.
So the useful way to read the dates is as a cold season, not a growing season. The mean daily minimum of the coldest month is 46.1°F. That is cool for a tender tomato and mild for a bok choy, mizuna or tatsoi. These greens grow through that kind of winter, and a hard freeze is the exception.
That puts the main sowing window in the cool half of the year. Fall sowing starts once summer heat breaks, which is a signal you watch for rather than a date on a calendar. It continues through winter in succession sowings. Spring sowing can begin in late winter, around the same weeks the last-frost window opens, and should finish before heat takes over. This page has no verified date for the exact day heat breaks in your yard, and that is deliberate, because it moves from year to year.
For a first pass, treat the fall-through-winter stretch as your main season and late winter as the last good chance. Anything sown into hot weather is a gamble, and the next section explains why. For specific crops, The Best Asian Greens for Louisiana goes variety by variety.
What will not work here
Waiting for the last frost date before sowing spring greens. In most states that is sound advice. Here the window opens January 18 to February 8, and a gardener who waits for it to close has already burned weeks of the only cool stretch left. By the time a spring sowing in March gets going, heat is already pushing leafy greens toward flowering.
Summer sowing is the clearest failure. With a coldest-month minimum of 46.1°F, winter barely slows these plants, and the opposite end of the year does the damage. Hot weather and long days make brassicas bolt, sending up a flower stalk before the leaves are worth eating. Seed that sprouts in a hot August bed also gives seedlings a rough start, with soil that dries out within hours.
Counting back from a fall frost date does not work well either. Northern gardeners often sow a set number of weeks before first frost. Here that frost lands around the holidays, or never arrives, so the count is useless as a trigger. Use falling night temperatures and cooling soil instead.
Close spacing is another trap, and humidity is the reason. Louisiana winters are damp as well as mild. Packed rows hold moisture on leaves, which invites fungal leaf spots and rot, and the mild temperatures mean disease does not get shut down by a deep freeze. Crowded baby-leaf rows that thrive in a drier state can turn slimy here. Give heads and larger plants more room than a seed packet from another region suggests, and thin early.
Finally, do not count on a freeze to clean up pests. In about one winter in seven there is no freeze at all, and in the rest the freezes are usually brief. Caterpillars and flea beetles can stay active nearly year-round. A lightweight row cover over a fresh sowing does more for you than hoping for a cold snap.
What changes across Louisiana
The USDA Plant Hardiness Zone Map (2023 edition, based on 1991-2020 normals) runs from 8a to 10a across the state. That is three zones, with the zones themselves split into 5-degree halves, so there is no single Louisiana answer. The system uses one variable, the average annual extreme minimum temperature. It tells you how cold the worst night can get, not how long summer lasts.
The dates on this page come from a New Orleans reference station, so they describe the warm end of that spread. North Louisiana freezes far more reliably. A northern gardener sees a hard freeze most winters, so the “one year in seven with no freeze” figure does not apply. There the fall window ends earlier and the spring window opens later, and a gardener should shift accordingly: begin spring sowing a few weeks after the southern window, and protect fall plantings with row cover against the first hard freezes.
On the coast, the opposite adjustment applies. Warmer winters make for easier winter growing but a sharper summer cutoff, so spring sowings should finish earlier. Plants that sail through winter in a southern bed can bolt early in a warm March.
For the zone your address sits in, check the USDA map directly with your ZIP code rather than guessing from the state average. Then use it as one input among several. A zone speaks to winter lows, and your sowing window also depends on summer heat, which the zone does not measure.
Where to check this for your own county
Your state extension service holds the better answer. In Louisiana that is the LSU AgCenter, the land-grant extension system. Louisiana organizes by parish rather than county, so look for the office that serves your parish.
Two things matter when you get there. First, find the local planting calendar for vegetables, which will give sowing windows for your part of the state instead of a statewide average. Second, look for the varieties trialled near you. A variety that held up through a wet winter in one parish may not be the one to buy in another.
A parish recommendation beats a state one, and this page is the state one. It rests on one reference station and a handful of climate figures. A local extension agent knows your soil, your rainfall pattern and the pests active this year. If the two disagree, go with the local source. This page does not carry a verified list of LSU AgCenter variety trial results, so check that directly rather than assuming.
For the broader picture of crops, soil and care, Growing Asian Greens in Louisiana covers what the calendar leaves out.
Checking this against your own garden
What you see in your own bed outranks every date above. Three observations cost nothing and tell you a lot.
- Soil warmth by feel. Push your hand into the bed in the early morning. Cool and damp means conditions are good for sowing. Warm like bathwater means the heat has not broken, and seed will struggle. A bed that stays warm longer than your neighbor’s is probably in full sun or against masonry.
- The first male flowers on squash or cucumbers. If you grow either, the first flush of male blooms signals that warm-season growth has taken off in your yard. That is the cue that your greens are on borrowed time, and that spring sowings should already be done.
- The first true leaves. Seedlings put out a pair of seed leaves, then true leaves. If they appear quickly and stay compact, the bed suits the crop. If they stall, or the seedlings stretch and thin out, the spot is too shaded, too cold or too wet.
Keep notes on when each of these happens, even on a scrap of paper. After a year or two you will have a calendar that fits your lot better than any statewide table, and one year in seven you may find the “winter” never turned up at all.
Common questions
Can I grow Asian greens all winter in south Louisiana?
Generally yes. The mean daily minimum of the coldest month at the reference station is 46.1°F, and a 32°F freeze happens in 86.8 percent of years. A hard freeze can still damage plants, so keep row cover handy.
Do I need to wait for the last frost to sow in spring?
No. The last-frost window of January 18 to February 8 is a 30 to 70 percent band of 32°F freeze probability, and waiting for it to close wastes cool weeks. Sow in late winter, with cover for cold nights.
Is summer sowing ever worth trying?
It is a gamble. Heat is the limiting factor here, and hot weather pushes these greens to bolt. If you try, use shade and frequent watering, and expect weaker results than from a fall sowing.
Is the north Louisiana calendar different?
Yes. North Louisiana freezes far more reliably, and the state spans USDA zones 8a to 10a. This page does not have a verified northern date set, so confirm with your parish extension office.