Sow Asian greens in Mississippi in two windows: late winter into early spring, and again from late summer into fall. Summer is the gap. At the Jackson reference station, the last spring freeze falls between March 6 and March 22, and the first fall freeze between November 7 and November 22. Those are reference-city figures. Your county will differ.
The short answer for Mississippi
Those frost dates come from NOAA’s 1991-2020 Climate Normals, and they are a probability, not a schedule. They mark the 30 to 70 percent band of the odds of a 32°F freeze. Within that stretch a freeze is a coin flip, more or less. Before it, a freeze is still likely. After it, a freeze is increasingly unlikely, but still possible. The figures come from one airport weather station, so treat them as the reference-city numbers and not a statewide guarantee.
| Event | Reference-city window (Jackson) | What it measures |
|---|---|---|
| Last spring frost | March 6 to March 22 | 30-70% band of 32°F freeze probabilities |
| First fall frost | November 7 to November 22 | 30-70% band of 32°F freeze probabilities |
Spring sowing
Asian greens such as bok choy, tatsoi and mizuna shrug off light frost, so you don’t need to wait for the spring window to close. Sow in late winter and let the March window arrive while seedlings are small and tucked in. The goal is to have heads or cut-and-come-again leaves ready before warm weather pushes them to bolt. A sowing that lands after the window has passed has less and less cool time left.
Fall sowing
Fall is the better season. Work backward from the November 7 to November 22 window, and sow late enough that germination isn’t happening in hot soil, but early enough that plants are established when nights turn cold. Mississippi’s long fall gives you room to stagger several sowings. Adjust earlier if you garden inland or north, since the reference figures run later in spring and earlier in fall for suburban and rural gardens, often by one to two weeks, and more at elevation.
Which types suit which window is a separate question, covered in The Best Asian Greens for Mississippi.
What will not work here
Mississippi’s short supply is cold, not warmth. Season length is generous: a gap of roughly eight months between the last and first freeze at the reference station. That removes the problem northern gardeners have, where slow varieties run out of season. Here the failures come from the other direction.
Summer sowing and late spring sowing
Sowing in the heat of summer is the clearest dud. Hot soil sours germination for many Asian greens, and the plants that do come up race to flower. A bed sown in late spring, after the March window has long closed, meets the same wall. The plants are only a few weeks old when real heat arrives, and they bolt before they size up. If a seed packet says “sow after danger of frost,” ignore it for these crops. For Asian greens, that advice points you at the wrong season.
Close spacing and weekly watering habits
Humidity is the second killer. Mississippi air stays wet through much of the growing year, and tightly packed rows trap that moisture around leaves. Downy mildew, leaf spots and soft rot at the base follow. Spacing that works in a dry western garden can fail here. Give plants room for air to move, water at the soil line in the morning and skip overhead sprinkling in the evening.
Water is rarely the shortage. A gardener who learned to water deeply once a week in a drier climate can drown seedlings in a wet Mississippi spring, especially in heavy soil that drains slowly. Raised beds or a slightly mounded row help. Flea beetles, which chew small holes in young leaves, also thrive in warm spring conditions, so row cover is worth setting out early.
One more trap: trusting the airport date. If you garden in a low spot or a rural pocket, a freeze can show up after the reference window in spring and before it in fall. Do not stake a tender seedling on March 22.
The coldest-month figure is mild. The mean daily minimum of the coldest month at Jackson is 36.6°F, an average night above freezing. That is not the record low, and individual nights still dip below 32°F, but it explains why hardy greens often survive winter here without protection.
What changes across Mississippi
A single Mississippi garden does not exist. The USDA Plant Hardiness Zone Map (2023, built on 1991-2020 normals) places the state in zones 7b to 9a. That spans several half-zone steps, from the cooler north to the Gulf Coast, and the zone rests on a single variable: the average annual extreme minimum temperature. So there is no single answer for the whole state. There is a spread.
Toward the north, expect later spring warmth, earlier fall freezes and colder winter lows. A reader there should shift fall sowings earlier, so plants have size before the frost window arrives, and give spring sowings a little more patience. Elevation pushes the same direction. Cold air also pools in hollows, so a low corner of a property can lag behind a ridge a hundred yards away.
Closer to the coast, winters are milder, and the fall season stretches later. Greens can stay productive deeper into winter, but the heat comes sooner in spring and lingers longer in fall, so bolting is the tighter constraint. The wet, humid air makes disease pressure heavier too.
Which zone are you in? This page cannot tell you. Look up your location on the USDA Plant Hardiness Zone Map and read the result for your own address, not the state label. Then use the reference dates above as a starting point and nudge them toward your result. For a broader look at the whole crop group, see Growing Asian Greens in Mississippi.
Where to check this for your own county
Start with Mississippi State University Extension, the state’s land-grant extension service. Its county offices are staffed by people who know the soils, pests and weather of your part of the state, and that local knowledge outranks any single table of dates.
Two things are worth looking for there. The first is a local planting calendar for fall and spring vegetables, ideally one written for your region of Mississippi. The second is a list of varieties trialled in your county or nearby, since a cultivar that holds up in the Delta may not do the same in the hills. If your county office can’t point you to a calendar that mentions Asian greens specifically, ask for the cool-season vegetable guidance, because these crops follow the same cool-weather rhythm as cabbage and kale.
This page does not have a Mississippi extension calendar specific to Asian greens. The extension calendars in our research are Clemson lawn calendars for South Carolina, which cover bermudagrass, zoysiagrass, centipedegrass and St. Augustinegrass, so they do not apply here, and borrowing a neighbor’s dates would only dress up a guess.
A county recommendation beats a state one. This page is the state one: a reference-city set of dates, softened by general reasoning. Use it to plan your season and the extension office to confirm it.
Checking this against your own garden
Your own observations outrank every date above. Three of them cost nothing and need no instruments.
- Soil warmth by feel. Push your hand a few inches into the bed in the morning. If it feels cold and clammy, spring seeds will sit and rot. If it feels warm even before midday, you are past the cool window. In fall, soil that still feels like bathwater means it is too early to sow. Comparing beds tells you which spot warms first.
- The first male flowers on nearby trees. Oaks and pecans shed pollen from dangling catkins. Watching when they open in your own yard tells you how your microclimate runs compared with the reference city. Note the date each year and the pattern becomes your own calendar.
- The first true leaves. Seedlings first show rounded seed leaves, then the shaped true leaves that look like the mature plant. Time from sowing to that point shows how fast a bed is growing. A bed that lags is cooler, shadier or wetter than the others.
Write those dates down for two seasons. By then, your garden’s record will tell you more than a weather station twenty miles away.
Common questions
Can I grow Asian greens through a Mississippi summer?
Not reliably. Heat pushes most of them to bolt and makes germination poor. Treat summer as a pause, and use shade cloth only if you are determined to try. Late summer sowings aimed at fall are the better plan.
Will Asian greens survive a Mississippi winter?
Often, yes. The mean daily minimum of the coldest month at Jackson is 36.6°F, though individual nights dip lower. Hardy types usually handle light frost, and row cover adds a margin. Your zone and county matter, so check them.
Are the frost dates on this page guaranteed?
No. They are the 30-70% band of NOAA’s 32°F freeze probabilities for one reference station. A freeze can still come after the spring window or before the fall one, and suburban or rural gardens commonly see later spring and earlier fall frosts by one to two weeks.
Where do I find a calendar for my county?
Contact your county office through Mississippi State University Extension and ask for its cool-season vegetable calendar and any variety trials run nearby.