US Grow Zones

McKinney, Texas: planting zone & frost dates

Last updated · Sources: PRISM/OSU 2023 ZIP zone listings; NOAA NCEI 1991–2020 Climate Normals (station USC00415766); U.S. Census Bureau — see methodology

McKinney is in USDA plant hardiness zone 8b, where the average coldest winter night reaches 15 to 20°F (-9.4 to -6.7°C). The typical last spring frost is around Mar 26 and the first fall frost around Nov 7.

Hardiness zone8B15 to 20°F
Last spring frostMar 2630% chance of frost after
First fall frostNov 730% chance of frost before
Growing season241 daysmedian frost-free days

Frost dates

ProbabilityLast spring frost (32°F)First fall frost (32°F)
Safer (10% risk)Apr 5Oct 27
Typical planning date (30% risk)Mar 26Nov 7
Median (50%)Mar 17Nov 15

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 MCKINNEY MUNICIPAL AIRPORT, TX (USC00415766), 4.3 mi (6.9 km) from the city center and 16 ft higher than the city center (+5 m). Record used for the 1991–2020 normals: 11 years.

Frost probability in spring and fall, McKinney, TXChance of a 32°F frost in McKinney, TX, NOAA 1991–2020. Spring: the chance of another frost falls from 90% on Feb 27 to 10% on Apr 5. Fall: the chance that the first frost has arrived rises from 10% on Oct 27 to 90% on Dec 5.0%50%100%Spring: later frostFeb 15Mar 1Mar 15Apr 130%: Mar 26Fall: frost arrivedNov 1Nov 15Dec 1Dec 1530%: Nov 732°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 USC00415766.
Frost-free growing season in McKinney, TX1 in 10 risk: Apr 5 to Oct 27 (205 days); 3 in 10 risk: Mar 26 to Nov 7 (226 days); Median (50%): Mar 17 to Nov 15 (243 days); No 28°F freeze: Mar 4 to Nov 30 (271 days). In 9 of 10 years the 32°F-free season is at least 213 days.Frost-free days, spring to fallJFMAMJJASOND1 in 10 risk205 days3 in 10 risk226 daysMedian (50%)243 daysNo 28°F freeze271 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 McKinney

All 5 ZIP codes covering McKinney are in zone 8b.

ZIP codes in McKinney and their zones
ZIPZoneShare of city land
750718b40.8%
750698b23.6%
750728b17.6%
750708b16.8%
754548b1.1%

Vegetable planting calendar for McKinney

Dates are counted from the 30%-risk frost dates above (last frost Mar 26, first frost Nov 7). Shift a week later in cold spots or low-lying ground.

CropStart indoorsTransplant / plant outDirect sowFall crop sow/plant
TomatoJan 29 – Feb 12Apr 2 – Apr 16——
PepperJan 15 – Jan 29Apr 9 – Apr 23——
LettuceFeb 12 – Feb 26Mar 12 – Apr 2Feb 26 – Apr 9Aug 29 – Sep 26
Green Beans——Apr 2 – May 7Aug 15 – Aug 29
Sweet Corn——Apr 2 – Apr 30—
Zucchini & Summer SquashFeb 26 – Mar 5Apr 2 – Apr 16Apr 2 – Apr 23Aug 15 – Aug 29
CucumberFeb 26 – Mar 5Apr 9 – Apr 16Apr 2 – Apr 23Aug 15 – Aug 29
Carrot——Mar 5 – Apr 9Aug 15 – Aug 29
OnionJan 1 – Jan 15Feb 26 – Mar 12——
Potato—Feb 26 – Mar 19——
BasilFeb 12 – Feb 26Apr 9 – Apr 23Apr 9 – Apr 30—
Spinach——Feb 12 – Mar 12Sep 12 – Oct 10
KaleJan 29 – Feb 12Feb 26 – Mar 19Feb 26 – Mar 19Aug 29 – Sep 26
BroccoliJan 29 – Feb 12Mar 12 – Apr 2—Aug 15 – Aug 29
Peas——Feb 12 – Mar 5Aug 29 – Sep 12
EggplantJan 15 – Jan 29Apr 9 – Apr 23——
CabbageJan 29 – Feb 12Feb 26 – Mar 12—Aug 15 – Aug 29
Radish——Feb 19 – Apr 9Sep 26 – Oct 24
Strawberry—Feb 26 – Mar 19——
Beets——Mar 5 – Apr 16Aug 29 – Sep 12

Nearby cities in Texas

More: all Texas cities · other zone 8b cities: Dallas, TX, Fort Worth, TX, El Paso, TX, Virginia Beach, VA, Arlington, TX, Plano, TX, Irving, TX, Garland, TX

McKinney gardening questions

When is the last frost in McKinney, TX?

Plan around Mar 26. At NOAA's Mckinney Municipal Airport, TX station, 4.3 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 17, and after Apr 5 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Mar 4. The 90% and 10% dates are 37 days apart, close to the 36-day median for cities on this site.

When should I plant tomatoes in McKinney, TX?

Start seeds indoors Jan 29 – Feb 12 and set transplants outside Apr 2 – Apr 16, once nights stay above 50°F and the soil is near 60°F. That leaves 226 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 McKinney?

About 241 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 213 days, and in 1 year in 10 it runs 268 days or more. In fall there is a 10% chance of frost by Oct 27 and a 30% chance by Nov 7. That ranks 47th longest of 55 Texas cities on this site.

When should I plant a fall garden in McKinney?

Count back from the first fall frost (Nov 7): transplant broccoli Aug 15 – Aug 29; sow kale Aug 29 – Sep 26; sow lettuce Aug 29 – Sep 26; sow radishes Sep 26 – Oct 24. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 30. How the math works: succession and fall planting.

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

Yes. Most of McKinney was zone 8a on the 2012 map and is zone 8b on the 2023 map — half a zone warmer, like about 56% of U.S. ZIP codes. The shift comes from a newer 1991–2020 averaging period plus more weather stations and better mapping; it does not mean last frost comes earlier. Why the 2023 map is warmer.

How does McKinney compare with Allen, TX?

Both are in zone 8b. The typical last spring frost in McKinney (Mar 26) comes about the same time as in Allen, TX (Mar 27), 6 miles away, and the first fall frost is Nov 7 versus Nov 5. The two cities use different NOAA stations.