March 28 looks like a finish line if you’ve circled it as Little Rock’s last frost date, but that number only marks a 30-70% probability, not a promise the cold is done. The Ozark Plateau holds frost longer than that date suggests, the Delta lets go of it sooner, and even where the 32°F line holds, your tomato seedlings start flinching several degrees before the ground ever sees an actual freeze.
The frost window in Arkansas
At the Little Rock station, NOAA’s 1991-2020 climate normals put the last spring freeze (32°F) somewhere between March 12 and March 28, and the first fall freeze somewhere between November 7 and November 20. These are 30-70% probability windows, meaning frost has roughly that likelihood of occurring on either side of the range in a typical year, not a hard cutoff you can circle on a calendar.
Little Rock sits close to the center of the state in both latitude and elevation, so treat its numbers as a baseline rather than a promise. The Ozark Plateau and the Ouachita Mountains, in the north and west, sit higher and tend to hold cold air longer into spring and pick it back up earlier in fall, which shortens the practical growing season there compared with Little Rock. The lower-elevation Delta counties in the east often run the other direction, with a longer frost-free stretch.
The 36°F threshold for tender plants
A 32°F freeze is what NOAA measures for its normals, but it is not the number that matters most for a tomato seedling. The National Weather Service office covering Little Rock also tracks a lighter, 36°F frost threshold, and for that measure the safe window runs from April 3 through October 31. Tender crops can suffer real damage at 36°F even though the air never technically drops to freezing, so use the later, tighter dates for anything that cannot tolerate a chill.
Counting from the earliest possible last frost to the latest possible first fall frost gives a season as long as 253 days. Counting from the latest last frost to the earliest first fall frost gives as few as 224 days. That roughly 224-to-253-day range is what you actually have to work with, and it also determines how many rounds of a fast crop you can fit into one bed, a point worth keeping in mind as you pick varieties later in the season.
Cool-season crops
Peas, spinach, lettuce, the brassica family (broccoli, cabbage, kale, collards) and root crops like carrots, beets, radishes and turnips can all go into the ground before the last frost date, because their seedlings tolerate a light frost that would kill a tomato outright. The trick is timing them off the frost date itself, not off a fixed month, since Little Rock’s own last-frost window swings by more than two weeks.
Working from the frost date instead of the calendar
Peas are usually sown about a month ahead of the last frost. Counting a month back from Little Rock’s March 12-28 window puts that sowing date somewhere in mid-to-late February, earlier if your local last frost tends to fall on the early side of the range, later if it runs long. Spinach and lettuce follow similar logic and can often go in slightly earlier than peas, since both germinate in cold soil and simply sit and grow slowly until the weather turns.
Not all these crops share the same tolerance. Spinach and kale can shrug off temperatures that would turn lettuce leaves to mush, so it makes sense to plant the hardiest crops earliest and save lettuce for a week or two later in the same cool stretch.
Brassica transplants, started indoors a few weeks earlier, usually go into the garden a few weeks before the last frost, timed so the seedlings reach the garden after the coldest nights have passed but while the air is still cool enough to keep them from bolting. Root crops are sown directly and tolerate a very early start, since the seed itself sits dormant in cold soil without harm.
- Peas: direct-sown, tolerate a hard frost once seedlings are up
- Spinach and lettuce: direct-sown or transplanted, tolerate a light frost
- Broccoli, cabbage and kale: transplanted, young plants tolerate a light frost
- Carrots, beets, radishes and turnips: direct-sown, seed unharmed by cold soil
None of these crops need to wait for soil to warm the way tomatoes and squash do. Their limiting factor is day length and cold tolerance, not soil temperature, which is why they can go in weeks ahead of the frost-sensitive crops that fill the rest of the garden once the danger of freezing has passed.
Warm-season crops
Tomatoes, peppers, squash, beans and corn are killed outright by a 32°F freeze and set back by anything close to it, so the frost date is the first hurdle, not the only one. Soil temperature is the second, and it lags behind air temperature by days or weeks depending on how wet and shaded the ground is. A tomato transplant set into soil that only just thawed sits and sulks even on a sunny, frost-free afternoon, so wait for the ground itself to warm rather than watching the forecast alone.
Counting back for indoor starts
Tomato seed is usually started indoors six to eight weeks before transplanting. Using the transplant window worked out for varieties suited to this territory, late March to mid April, that puts the indoor sowing date somewhere in early-to-mid February for the early end of the window and late February for the later end. Peppers run on a similar clock but often want an extra week or two indoors, since their seed germinates more slowly in cool soil.
Several tomato varieties suited to a range of season lengths all fit inside Arkansas’s frost-free window once you count forward from a late-March-to-mid-April transplant date. The table below shows the arithmetic for five of them, from the earliest ripening to the latest, each counted against the shorter end of Little Rock’s fall frost window for a conservative margin.
| Variety | Days to Maturity (from transplant) | Type | Approx. First Ripe | Margin Before Fall Frost |
|---|---|---|---|---|
| Sakura | 55 | Indeterminate | Early June | 155 days |
| Sun Gold | 57 | Indeterminate | Early June | 153 days |
| Cherokee Purple | 72 | Indeterminate | Late June | 138 days |
| Celebrity Plus | 78 | Determinate | Late June | 132 days |
| San Marzano II | 78 | Indeterminate | Late June | 132 days |
Those margin figures are calculated against the shortest end of Little Rock’s fall frost window (November 7), so treat them as a conservative floor. If your first fall frost tends to arrive on the later side, closer to November 20, every variety in the table gains almost two more weeks of margin.
Peppers, squash, beans and corn follow the same logic as tomatoes even without named cultivars on this page. Sweet corn and squash seed both germinate poorly in cold soil and are more likely to rot than to simply wait it out, so gardeners often hold off on direct-sowing either crop until the soil has had real time to warm, longer than the tomato transplant window alone would suggest. Beans are usually direct-sown once the risk of a 32°F freeze has passed, for the same reason. A pepper transplant set out too early often just sits at the same size for weeks rather than dying outright, which can be more frustrating than an obvious loss.
Season length also affects how many rounds of a fast crop fit into one year. A 55-day variety like Sakura leaves enough margin, even planted at the tail end of the transplant window, to consider a second planting later in the season, while a 78-day variety like San Marzano II uses up most of the available window in a single pass.
The fall planting window
Fall planting works backward from the first fall frost instead of forward from the last one. Little Rock’s first fall freeze falls between November 7 and November 20, according to NOAA’s 1991-2020 normals, so a fall crop’s days-to-maturity number gets subtracted from that range, then padded with extra time because plants grow more slowly as day length and temperature drop in September and October.
An example calculation
Take a fall crop that needs 60 days to reach harvest under summer conditions. Add roughly two extra weeks to cover the slower growth of shortening fall days, for a total of about 74 days needed before frost. Counting 74 days back from the early end of the frost window (November 7) lands in the last week of August. Counting 74 days back from the late end (November 20) lands in the first week of September. That gives a sowing window of roughly late August to early September for a 60-day fall crop, tighter if your own local frost tends to arrive early, looser if it runs late.
Fall is also when many gardeners plant garlic, though garlic works on an entirely different clock than the vegetables above. Garlic cloves go into the ground once the soil has cooled from summer heat but well before it freezes solid, rooting through fall and winter before bulking up the following late spring. Because garlic overwinters in the ground, it is not governed by the first fall frost date the way lettuce or broccoli are.
Crops that improve after a light frost
Kale, collards, Brussels sprouts, carrots, beets and spinach all handle a light frost without damage, and several of them actually taste better afterward. Cold temperatures push these plants to convert stored starches into sugars as a natural antifreeze response, which is why a kale leaf or a carrot pulled after the first frost of the season often tastes sweeter than the same plant harvested in warm weather. That makes the fall garden more forgiving of a frost date that arrives a little early than the spring garden is of one that lingers late.
Reading a planting calendar properly
A state-wide planting calendar, including this one, is built from a single weather station and averaged over thirty years. It tells you what is typical, not what will happen in your own yard this year. Arkansas’s terrain adds enough local variation that two gardens forty miles apart can have meaningfully different frost dates.
What actually shifts the date
Elevation is the biggest factor. Cold air is denser than warm air and drains downhill, so a garden in a low valley or hollow can see frost on nights when a garden on a nearby ridge stays clear. Large bodies of water moderate temperature nearby, delaying both the first frost in fall and the last frost in spring for gardens close to a lake or a major river. Urban areas hold heat overnight from pavement and buildings, which is why a garden in the middle of a city often runs milder than open countryside a short drive away. A late cold snap can also undo all of this at once, arriving weeks after the statistical window has closed and catching a garden that jumped the gun on tender transplants.
None of this means the calendar is useless. It means treating the date range as a range, not a single edge to plant right up against. A gardener in Delaware works from a completely different coastal frost pattern (see the Delaware planting calendar), and a Minnesota gardener plans around a frost-free season barely half as long as Arkansas’s (see the Minnesota planting calendar). What matters is watching your own garden: track when frost actually hits your yard for a season or two, note which corners clear first in spring, and adjust the calendar dates to match what you observe rather than the other way around.
Local help
County-level frost dates, soil testing and planting guidance specific to your part of Arkansas are available through the University of Arkansas System Division of Agriculture’s Cooperative Extension Service. Its county offices can test your soil for pH and nutrient levels before you plant, which matters more to a harvest than shaving a few days off a planting date. For more on growing conditions across the state, see our Arkansas guides.
Common questions
Can I plant tomatoes before the last frost date if I use row covers?
Row covers and cloches buy you some protection, usually enough to handle a light dip a few degrees below freezing for a night, but they do not make the last-frost date irrelevant. A hard freeze on an exposed plant under thin fabric can still cause damage, and soil temperature underneath a cover often stays cooler than gardeners expect. Treat covers as insurance for a marginal night, not a reason to plant weeks ahead of Little Rock’s March 12-28 window.
What’s the actual difference between a frost date and a freeze date?
NOAA’s 32°F figure is a freeze, cold enough to kill most tender plant tissue outright. A frost can form on surfaces even when the air temperature stays a few degrees above freezing, particularly on clear, calm nights, which is why the National Weather Service’s 36°F threshold for Little Rock (April 3 to October 31) is the more cautious number to plan around for tender crops.
Do gardeners in north Arkansas use the same dates as Little Rock?
No. Little Rock’s numbers come from a single station near the center of the state, and higher, more northern parts of Arkansas typically see a later last frost and an earlier first fall frost than Little Rock, which shortens the growing season there. Check with your county extension office for a reading closer to home.
Can I actually grow a slower tomato like San Marzano II here?
Yes. San Marzano II needs 78 days from transplant, and setting it out in the late-March-to-mid-April window common for this territory still leaves well over 130 days before Little Rock’s first fall frost arrives. Even a cool, slow start rarely eats up that much margin.
My last frost date already passed but it’s still cold at night, what happened?
Nothing unusual. NOAA’s frost dates are a probability range built from thirty years of data, not a guarantee, and a given year can still bring a frost after the statistical window closes. That is exactly why the range spans more than two weeks rather than naming a single day, and why it pays to watch an actual forecast rather than a calendar once you are close to the date.