Frost dates · USDA zone 6b
Frost dates for Olathe, KS
Olathe, KS sees its last 32 °F night of spring around April 13 and its first of fall around October 24 — a 193-day freeze-free season in a typical year.
Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.
Freeze odds, by date
| Odds | Last spring freeze after | First fall freeze before |
|---|---|---|
| 9 years in 10 | Mar 30 | Nov 4 |
| Median — 1 year in 2 | Apr 13 | Oct 24 |
| 1 year in 10 | Apr 29 | Oct 10 |
The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 193 days median, at least 173 in 9 years of 10, at least 211 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of Apr 3 and first of Nov 2.
Olathe planting calendar, 2027
Every row runs from the median last frost (Apr 13) and median first frost (Oct 24) above, using each cultivar's days to maturity. Same engine as the Plan Builder.
| Crop | Start indoors | Transplant / plant | First harvest | Days |
|---|---|---|---|---|
| Hardneck GarlicSiberian (porcelain hardneck) | — | Oct 15prior fall | Jun 12 | 240 from sow |
| Spanish OnionYellow Sweet Spanish (long-day) | Jan 19 | Mar 16 | Jul 4 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | Apr 13 | May 13 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Mar 30 | Mar 30 | May 14 | 45 from sow |
| Genovese BasilGenovese | Mar 16 | Apr 27 | Jun 26 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Feb 16 | Apr 20 | Jul 4 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Feb 2 | Apr 27 | Jul 31 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Feb 16 | Apr 20 | Jul 4 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Feb 16 | Apr 20 | Jul 9 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Feb 16 | Apr 20 | Jul 9 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Mar 30 | Mar 30 | Jun 8 | 70 from sow |
| TomatilloToma Verde | Mar 2 | Apr 20 | Jun 29 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Mar 2 | Apr 20 | Jul 4 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Mar 2 | Apr 20 | Jul 9 | 80 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.
What sauce can Olathe grow?
Each sauce, scheduled for a Olathe container garden: when the first seeds go in and when enough fruit has ripened for one batch.
Olathe frost questions
When is the last frost in Olathe, KS?
The median last 32 °F freeze at OLATHE JOHNSON CO AP, KS is April 13: half of years see a later one. One year in ten, a freeze still comes after April 29; nine years in ten, it comes after March 30. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in Olathe, KS?
The median first 32 °F freeze of fall is October 24. One year in ten it arrives before October 10; nine years in ten, before November 4.
How long is the growing season in Olathe, KS?
193 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 173 days; one year in ten, at least 211 days.
What growing zone is Olathe, KS?
USDA hardiness zone 6b, per the 2023 USDA Plant Hardiness Zone Map for ZIP 66061. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.
When should I plant tomatoes in Olathe, KS?
Start Roma VF (determinate paste) seeds indoors around Mar 2 and transplant around Apr 20, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Apr 29. First ripe fruit lands around Jul 4.
When should I plant peppers in Olathe, KS?
Sow jalapeño indoors on a heat mat around Feb 16; transplant no earlier than Apr 20, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Jul 4.
Nearby in Kansas
- Lenexalast frost Apr 10
- Overland Parklast frost Apr 10
- Shawneelast frost Apr 16
- Kansas Citylast frost Apr 16
- Lawrencelast frost Apr 12
- Topekalast frost Apr 12
All Kansas frost dates → · How frost-date math drives a sowing calendar →