When to Plant a Fall Vegetable Garden: Planting Dates by City

Plant a fall vegetable garden by counting back from your area’s median first fall frost: take each crop’s days to maturity, add about 14 days because growth slows in fall, and add 14 more for frost-tender crops such as beans and squash. From Madison to Boston that means bush beans by late July to late August, broccoli transplants a few days later, spinach by mid-August to mid-September and radishes by about September 1 to October 1. Atlanta and New York can sow beans until late August or early September, Dallas until mid-September.

Every top guide and Google’s AI Overview give that rule but no date for any place. We ran the extension formula on NOAA’s 1991–2020 frost normals for 20 cities¹ and checked it against seven published local calendars. We also tested the 14-day frost-tender allowance against frost odds in 39,024 ZIP codes.

How to calculate your fall planting date

Nebraska Extension, Virginia Cooperative Extension and Oregon State all use the same count-back.^2,3,4 Add up:

• Days to maturity from the seed packet, for the earliest variety you can find.
• Days to grow your own transplants, if you start seedlings yourself.
• The harvest period you want, if you plan to pick for weeks rather than once.
• A fall factor of about 14 days for slower growth in cooler, shorter days.
• A frost-tender factor of 14 days for crops a light frost kills.

The total is the number of days to count back from the first expected fall frost. Nebraska’s NebGuide G1343 explains the last step for beans, corn, cucumbers, tomatoes and squash: they

must mature at least two weeks before frost in order to produce a reasonable harvest

The Old Farmer’s Almanac uses a smaller fall factor, a week or two, and adds 7 to 10 days if you want to harvest over time.¹³

Days to maturity: from seed or from transplant

For tomatoes, peppers, eggplant, melons, broccoli, cabbage, cauliflower and Brussels sprouts, the number on the packet usually counts from transplanting, says the University of Maryland; for other crops it counts from direct seeding.⁷ If you grow your own brassica transplants, add the time to raise them. Nebraska says seedlings can be grown in five to six weeks,² and Iowa State sows them indoors six to eight weeks before the fall planting date.⁵ Our seed-starting guide covers lights and trays.

Fall planting dates for 20 US cities

The table counts back from the median first 32°F frost at the NOAA station nearest each city. It uses the low end of Iowa State’s days-to-maturity ranges: 50 days for bush beans, 60 from transplanting for broccoli, 45 for spinach and 25 for radishes.⁵

A different variety changes the date one for one: a 60-day bean instead of a 50-day bean moves the deadline 10 days earlier. Gardens in a valley, on a hilltop or far from the station can differ by a week or more, so look up the first fall frost for your ZIP code and count back the same way. Seattle, Portland, Sacramento and Houston are left out of this table on purpose; see short days and warm-winter gardens.

Which frost date to count back from

A median frost date is a coin flip: in half of years the first 32°F night comes earlier. Our guide to what frost-date odds mean explains the probabilities.

Sources pick different dates. Nebraska, Iowa State and the Almanac count from the average first frost.^2,5,13 Piedmont Master Gardeners in central Virginia put the average first frost there at October 10 to 15 and pick October 10 “to be on the safe side.”⁹ NOAA’s normals for the Free Union station near Charlottesville put the median at October 24, so October 10 is in fact the 10% date there.¹ Cornell Cooperative Extension in Warren County, New York, counts from the 28°F killing frost and adds no fall factor.⁸

We checked what the frost-tender factor really buys. Across 39,024 contiguous-US ZIP codes where fall frost is normal, the 10% first-frost date falls a median 14 days before the median date (middle half: 13–16 days).¹ So “average frost minus 14 days” is, in a typical ZIP code, the date with only a 1-in-10 chance of an earlier frost.

Frost-tolerant crops get a bonus at the other end. The 28°F hard freeze, which the National Weather Service says kills most vegetation,¹⁵ comes a median 11 days after the first 32°F night (middle half 10–13 days).¹ Our guides on frost vs. freeze and when to cover plants for frost cover that window.

Hardy, semi-hardy and tender fall crops

Iowa State Extension sorts fall vegetables into three groups. Tender crops are hurt by a light frost; semi-hardy crops take the upper 20s°F; hardy crops survive the mid to low 20s.⁵ Nebraska puts the hardy limit near 20°F and the semi-hardy limit at a light frost of 30 to 32°F.²

Days to maturity are Iowa State’s ranges; the count-back adds the 14-day fall factor to the low end, plus 14 days for tender crops.^5,2 The groups don’t always agree: Iowa State lists carrots as semi-hardy, while Nebraska lists them with the hardy crops, along with turnips and rutabagas.^5,2

Hardy crops can be harvested after the first frost, and some, Iowa State says, as late as November.⁵ Virginia Cooperative Extension notes that cabbage, broccoli, spinach and Brussels sprouts don’t need to be picked the moment frost comes.³ Tender crops are the opposite: pick ripe tomatoes, squash, peppers and cucumbers when the first frost is forecast.³

How the formula compares with local calendars

We ran the formula for seven places that publish their own fall planting dates and compared the latest date each calendar gives.^5,6,7,4,8

Frost-tender beans: the formula lands within 2 days of the calendar in Ames, Carbondale and Warren County, New York. In Maryland it matches within a day when we use the October 25 frost date that the University of Maryland built its central-Maryland calendar on;⁷ NOAA’s Frederick median, November 6, would allow 13 more days. Northern and central Illinois list snap beans with slower crops such as broccoli, cabbage and carrots, so their bean dates (marked * in Table 3) run 2 to 4 weeks earlier.⁶

Frost-tolerant spinach: four of the seven calendars let you sow 12 to 28 days later than the formula; Rockford, Frederick and Portland are within 3 days. That fits Iowa State’s note that semi-hardy crops are often harvested after the first frost.⁵ Treat the spinach and radish dates in Table 1 as safe dates for a full crop, and push them a week or two later if you’re happy to harvest small leaves or cover the bed.

One more check: an Ohio State educator in Hocking County put the frost-free date “around the middle of October,” with “a little under 100 days” left on July 9.¹⁴ NOAA’s median for Logan, Ohio, is October 14, which is 97 days after July 9.¹

Short days: the second deadline

Frost isn’t the only thing that ends a fall garden. Oregon State uses the same formula but warns that crops need

time to mature before cold weather and short days curtail growth

The UC Master Gardeners of Contra Costa County use Eliot Coleman’s “Persephone period,” the weeks when daylight is under 10 hours, because

most plants need more than 10 hours of daily sunlight for growth

They give November 20 to January 22 for Contra Costa, from the US Naval Observatory’s tables.¹⁰ Our day-length calculation gives November 20 to January 23 there, so we used it for every ZIP code.

Nationally, days drop below 10 hours before the median first frost in 7% of ZIP codes where fall frost is normal, but in 75% of California ZIP codes and about 40% in Washington, Oregon and Nevada. In Texas, Florida, Georgia and Louisiana it never happens: frost comes first.¹

That is why the frost count-back runs late on the Pacific coast. For Oregon’s western valleys, Oregon State lists snap beans through July, broccoli through August, and spinach and radishes in September.⁴ With Portland’s December 1 median frost, the formula gives September 14 for beans, September 18 for broccoli and October 23 for radishes: 2½ to 6½ weeks later. Spinach (October 3) is the only close match. West of the Cascades and in California’s valleys, use your county’s extension calendar.

Warm-winter gardens: Texas, the Gulf Coast and Florida

Where frost comes in December or not at all, fall is a second main season and heat sets the start. Frost is rare at 4% (1,540 of 40,564) of contiguous-US ZIP codes.¹ Texas A&M AgriLife publishes fall dates for five regions: the last optimum date for tomato, pepper and eggplant transplants runs from June 25 in Region I to September 1 in Region V, and for broccoli, cabbage, cauliflower and Brussels sprouts from August 1 to November 20.¹¹ It also says fall crops generally do better from transplants, and that tomatoes and peppers should always be transplanted.¹¹

In Louisiana, LSU AgCenter makes August and September the main months and starts tomatoes, pumpkins, peas and okra a month or two earlier. Tomatoes, peppers and eggplant can take two to two and a half months from transplanting to the first fruit, it notes.¹² For spring tomato timing, see when to plant tomatoes. Texas A&M and LSU AgCenter also recommend a fall potato crop, planted from mid-August; see when to plant potatoes.

Getting fall seeds up in summer heat

Fall gardens are sown in the hottest, driest weeks, so germination is the hard part.

• Water first. Plant after a rain or soak the bed the day before; Virginia Cooperative Extension suggests a shallow trench to hold moisture.³
• Sow deeper. Cover seeds about twice as deep as in spring.^2,3
• Cool the soil. Lettuce, peas and spinach germinate poorly above 85°F soil. Shade the row with a raised board or a light mulch and remove it when sprouts appear.²
• Pre-sprout. Sprouting seeds indoors first can save two to five days.³

Insects don’t take the fall off. Nebraska warns that cabbage worms and cabbage loopers can strip new brassica transplants, and that cucumber beetles and squash bugs peak in August; a lightweight floating row cover over new plantings keeps many of them out.²

Next steps

Find your median first fall frost with our frost dates by ZIP code tool, then count back with Table 2. Garlic goes in later, around the first frost: see when to plant garlic. More in our vegetable guides, frost and freeze guides and the methodology page.