US Grow Zones

Lawton, Oklahoma: planting zone & frost dates

Last updated · Sources: PRISM/OSU 2023 ZIP zone listings; NOAA NCEI 1991–2020 Climate Normals (station USC00345063); U.S. Census Bureau — see methodology

Lawton is in USDA plant hardiness zone 7b, where the average coldest winter night reaches 5 to 10°F (-15.0 to -12.2°C). The typical last spring frost is around Apr 3 and the first fall frost around Nov 1.

Hardiness zone7B5 to 10°F
Last spring frostApr 330% chance of frost after
First fall frostNov 130% chance of frost before
Growing season225 daysmedian frost-free days

Frost dates

ProbabilityLast spring frost (32°F)First fall frost (32°F)
Safer (10% risk)Apr 14Oct 21
Typical planning date (30% risk)Apr 3Nov 1
Median (50%)Mar 26Nov 7

How to read this: after the spring "10% risk" date, a 32°F frost happens in only about 1 year in 10. In fall, the "10% risk" date is the early end — a frost before it happens about 1 year in 10.

Frost data comes from NOAA station LAWTON, OK (USC00345063), 2.1 mi (3.4 km) from the city center and 10 ft higher than the city center (+3 m). Record used for the 1991–2020 normals: 14 years.

Frost probability in spring and fall, Lawton, OKChance of a 32°F frost in Lawton, OK, NOAA 1991–2020. Spring: the chance of another frost falls from 90% on Mar 4 to 10% on Apr 14. Fall: the chance that the first frost has arrived rises from 10% on Oct 21 to 90% on Nov 22.0%50%100%Spring: later frostFeb 15Mar 15Apr 1530%: Apr 3Fall: frost arrivedOct 15Nov 1Nov 15Dec 130%: Nov 132°F frost28°F hard freezeplanning date
Shaded areas show the chance of a 32°F frost: falling through spring, rising through fall. The dashed line is the 28°F hard-freeze curve. Data: NOAA 1991–2020 Normals, station USC00345063.
Frost-free growing season in Lawton, OK1 in 10 risk: Apr 14 to Oct 21 (190 days); 3 in 10 risk: Apr 3 to Nov 1 (212 days); Median (50%): Mar 26 to Nov 7 (226 days); No 28°F freeze: Mar 11 to Nov 16 (250 days). In 9 of 10 years the 32°F-free season is at least 200 days.Frost-free days, spring to fallJFMAMJJASOND1 in 10 risk190 days3 in 10 risk212 daysMedian (50%)226 daysNo 28°F freeze250 days
Frost-free window at three risk levels, plus the window between 28°F hard freezes. Read about what the probabilities mean.

Why your yard may differ from the station: microclimates.

Hardiness zone across Lawton

Lawton spans more than one half-zone. Share of the city's land area by zone (via its 4 ZIP codes): 7b (72%), 8a (28%). The headline zone is the one covering the most land. Look up your ZIP for your exact zone.

ZIP codes in Lawton and their zones
ZIPZoneShare of city land
735057b37.0%
735038a28.4%
735017b21.1%
735077b13.6%

Vegetable planting calendar for Lawton

Dates are counted from the 30%-risk frost dates above (last frost Apr 3, first frost Nov 1). Shift a week later in cold spots or low-lying ground.

CropStart indoorsTransplant / plant outDirect sowFall crop sow/plant
TomatoFeb 6 – Feb 20Apr 10 – Apr 24——
PepperJan 23 – Feb 6Apr 17 – May 1——
LettuceFeb 20 – Mar 6Mar 20 – Apr 10Mar 6 – Apr 17Aug 23 – Sep 20
Green Beans——Apr 10 – May 15Aug 9 – Aug 23
Sweet Corn——Apr 10 – May 8—
Zucchini & Summer SquashMar 6 – Mar 13Apr 10 – Apr 24Apr 10 – May 1Aug 9 – Aug 23
CucumberMar 6 – Mar 13Apr 17 – Apr 24Apr 10 – May 1Aug 9 – Aug 23
Carrot——Mar 13 – Apr 17Aug 9 – Aug 23
OnionJan 9 – Jan 23Mar 6 – Mar 20——
Potato—Mar 6 – Mar 27——
BasilFeb 20 – Mar 6Apr 17 – May 1Apr 17 – May 8—
Spinach——Feb 20 – Mar 20Sep 6 – Oct 4
KaleFeb 6 – Feb 20Mar 6 – Mar 27Mar 6 – Mar 27Aug 23 – Sep 20
BroccoliFeb 6 – Feb 20Mar 20 – Apr 10—Aug 9 – Aug 23
Peas——Feb 20 – Mar 13Aug 23 – Sep 6
EggplantJan 23 – Feb 6Apr 17 – May 1——
CabbageFeb 6 – Feb 20Mar 6 – Mar 20—Aug 9 – Aug 23
Radish——Feb 27 – Apr 17Sep 20 – Oct 18
Strawberry—Mar 6 – Mar 27——
Beets——Mar 13 – Apr 24Aug 23 – Sep 6

Nearby cities in Oklahoma

More: all Oklahoma cities · other zone 7b cities: New York, NY, Philadelphia, PA, Oklahoma City, OK, Nashville, TN, Washington, DC, Baltimore, MD, Albuquerque, NM, Tulsa, OK

Lawton gardening questions

When is the last frost in Lawton, OK?

Plan around Apr 3. At NOAA's Lawton, OK station, 2.1 mi from the city center, there is a 30% chance of a 32°F frost after that date. Half of springs have their last frost by Mar 26, and after Apr 14 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Mar 11. The 90% and 10% dates are 41 days apart, close to the 36-day median for cities on this site.

When should I plant tomatoes in Lawton, OK?

Start seeds indoors Feb 6 – Feb 20 and set transplants outside Apr 10 – Apr 24, once nights stay above 50°F and the soil is near 60°F. That leaves 212 days between the 30% frost dates, enough for most varieties including 80–85-day slicers. More: tomato planting dates by zone.

How long is the growing season in Lawton?

About 225 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 200 days, and in 1 year in 10 it runs 253 days or more. In fall there is a 10% chance of frost by Oct 21 and a 30% chance by Nov 1. That is the longest of the 6 Oklahoma cities on this site.

When should I plant a fall garden in Lawton?

Count back from the first fall frost (Nov 1): transplant broccoli Aug 9 – Aug 23; sow kale Aug 23 – Sep 20; sow lettuce Aug 23 – Sep 20; sow radishes Sep 20 – Oct 18. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 16. How the math works: succession and fall planting.

Did Lawton's hardiness zone change on the 2023 map?

No. Going by the zone that covers most of the city's land, Lawton is zone 7b on both the 2012 and the 2023 USDA maps (PRISM/OSU ZIP listings). About 42% of U.S. ZIP codes kept their half-zone in 2023. Why the 2023 map is warmer.

Is all of Lawton in zone 7b?

No. Zone 7b covers about 72% of the city's land; the rest is in 8a (28%), measured across the city's 4 ZIP codes. Check your own ZIP code in the table above or with the ZIP lookup.