Lee's Summit, Missouri: planting zone & frost dates
Lee's Summit is in USDA plant hardiness zone 6b, where the average coldest winter night reaches -5 to 0°F (-20.6 to -17.8°C). The typical last spring frost is around Apr 13 and the first fall frost around Oct 23.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | Apr 24 | Oct 14 |
| Typical planning date (30% risk) | Apr 13 | Oct 23 |
| Median (50%) | Apr 7 | Oct 29 |
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 LEES SUMMIT MUNI AP, MO (USW00053879), 2.7 mi (4.4 km) from the city center and 20 ft lower than the city center (-6 m). Record used for the 1991–2020 normals: 19 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Lee's Summit
All 5 ZIP codes covering Lee's Summit are in zone 6b.
Vegetable planting calendar for Lee's Summit
Dates are counted from the 30%-risk frost dates above (last frost Apr 13, first frost Oct 23). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Feb 16 – Mar 2 | Apr 20 – May 4 | — | — |
| Pepper | Feb 2 – Feb 16 | Apr 27 – May 11 | — | — |
| Lettuce | Mar 2 – Mar 16 | Mar 30 – Apr 20 | Mar 16 – Apr 27 | Aug 14 – Sep 11 |
| Green Beans | — | — | Apr 20 – May 25 | Jul 31 – Aug 14 |
| Sweet Corn | — | — | Apr 20 – May 18 | — |
| Zucchini & Summer Squash | Mar 16 – Mar 23 | Apr 20 – May 4 | Apr 20 – May 11 | Jul 31 – Aug 14 |
| Cucumber | Mar 16 – Mar 23 | Apr 27 – May 4 | Apr 20 – May 11 | Jul 31 – Aug 14 |
| Carrot | — | — | Mar 23 – Apr 27 | Jul 31 – Aug 14 |
| Onion | Jan 19 – Feb 2 | Mar 16 – Mar 30 | — | — |
| Potato | — | Mar 16 – Apr 6 | — | — |
| Basil | Mar 2 – Mar 16 | Apr 27 – May 11 | Apr 27 – May 18 | — |
| Spinach | — | — | Mar 2 – Mar 30 | Aug 28 – Sep 25 |
| Kale | Feb 16 – Mar 2 | Mar 16 – Apr 6 | Mar 16 – Apr 6 | Aug 14 – Sep 11 |
| Broccoli | Feb 16 – Mar 2 | Mar 30 – Apr 20 | — | Jul 31 – Aug 14 |
| Peas | — | — | Mar 2 – Mar 23 | Aug 14 – Aug 28 |
| Eggplant | Feb 2 – Feb 16 | Apr 27 – May 11 | — | — |
| Cabbage | Feb 16 – Mar 2 | Mar 16 – Mar 30 | — | Jul 31 – Aug 14 |
| Radish | — | — | Mar 9 – Apr 27 | Sep 11 – Oct 9 |
| Strawberry | — | Mar 16 – Apr 6 | — | — |
| Beets | — | — | Mar 23 – May 4 | Aug 14 – Aug 28 |
Nearby cities in Missouri
- Independence — zone 6b, last frost Apr 16, first frost Oct 22
- Kansas City — zone 6b, last frost Apr 10, first frost Oct 29
- Springfield — zone 6b, last frost Apr 16, first frost Oct 22
- Columbia — zone 6b, last frost Apr 12, first frost Oct 25
- O'Fallon — zone 6b, last frost Apr 16, first frost Oct 20
- St. Louis — zone 7a, last frost Apr 7, first frost Oct 31
More: all Missouri cities · other zone 6b cities: Columbus, OH, Indianapolis, IN, Boston, MA, Detroit, MI, Kansas City, MO, Cincinnati, OH, Pittsburgh, PA, Buffalo, NY
Lee's Summit gardening questions
When is the last frost in Lee's Summit, MO?
Plan around Apr 13. At NOAA's Lees Summit Municipal Airport, MO station, 2.7 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 Apr 7, and after Apr 24 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Mar 28. The 90% and 10% dates are 34 days apart, close to the 36-day median for cities on this site.
When should I plant tomatoes in Lee's Summit, MO?
Start seeds indoors Feb 16 – Mar 2 and set transplants outside Apr 20 – May 4, once nights stay above 50°F and the soil is near 60°F. That leaves 193 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 Lee's Summit?
About 202 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 180 days, and in 1 year in 10 it runs 224 days or more. In fall there is a 10% chance of frost by Oct 14 and a 30% chance by Oct 23. That ranks 4th longest of 7 Missouri cities on this site.
When should I plant a fall garden in Lee's Summit?
Count back from the first fall frost (Oct 23): transplant broccoli Jul 31 – Aug 14; sow kale Aug 14 – Sep 11; sow lettuce Aug 14 – Sep 11; sow radishes Sep 11 – Oct 9. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 7. How the math works: succession and fall planting.
Did Lee's Summit's hardiness zone change on the 2023 map?
Yes. Most of Lee's Summit was zone 6a on the 2012 map and is zone 6b 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 Lee's Summit compare with Independence, MO?
Both are in zone 6b. The typical last spring frost in Lee's Summit (Apr 13) comes about the same time as in Independence, MO (Apr 16), 11 miles away, and the first fall frost is Oct 23 versus Oct 22. Lee's Summit sits about 164 ft higher, which explains part of the gap. The two cities use different NOAA stations.