When to plant in Olathe, KS
USDA Zone 6bHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Olathe, Kansas — all computed from Olathe's nearest NOAA weather station.
In zone 6b, Olathe gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
OLATHE 3E · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Olathe’s own odds, recorded at OLATHE 3E.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 2 | Apr 19 | Apr 5 | Oct 2 | Oct 20 | Oct 31 |
| 32°F | Apr 24 | Apr 10 | Mar 27 | Oct 13 | Oct 29 | Nov 12 |
| 28°F | Apr 17 | Mar 31 | Mar 13 | Oct 23 | Nov 6 | Nov 25 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Olathe, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 8 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Olathe planting FAQ
When is the last spring frost in Olathe, KS?
On average, the last spring frost in Olathe is around April 10 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in Olathe, KS?
In Olathe, the first 32°F freeze of fall lands around October 29 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Olathe in?
Olathe is in USDA hardiness zone 6b. In zone 6b, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Olathe?
Olathe has about 202 frost-free days — a moderate growing season — between the average last spring frost (April 10) and first fall frost (October 29).
When should I plant tomatoes in Olathe?
For Olathe, sow tomatoes indoors about February 13–February 27 and move the seedlings out around April 17, after the last spring frost.
Never miss a window in Olathe
An email when it’s time to start seeds, transplant, and sow — timed to Olathe’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Lenexa · 9 km
- Overland Park · 11 km
- Gardner · 12 km
- Shawnee · 15 km
- Leawood · 17 km
- Merriam · 19 km
- Prairie Village · 20 km
- Grandview · 26 km
Frost dates recorded at OLATHE 3E, 5 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Olathe, KS — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00145972. Retrieved from https://blissgarden.com/kansas/olathe.