Frost Dates for Stillwater, OK
In Stillwater, OK, the average last spring frost is around Apr 5 and the average first fall frost around Oct 30, for a growing season of about 206 days. For frost-tender plants, wait until Apr 21, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Stillwater 2 W, OK weather station, 1 mile away, elevation 890 ft. Frost can come earlier in low spots and valleys and later near cities and large lakes.
Frost probability by date
Chance of a 32°F frost after the spring date, or before the fall date.
| Chance | Last spring frost | First fall frost |
|---|---|---|
| 10% | Apr 21 | Oct 16 |
| 20% | Apr 16 | Oct 21 |
| 30% | Apr 12 | Oct 24 |
| 40% | Apr 9 | Oct 27 |
| 50% | Apr 5 | Oct 30 |
| 60% | Apr 3 | Nov 2 |
| 70% | Mar 31 | Nov 5 |
| 80% | Mar 27 | Nov 10 |
| 90% | Mar 21 | Nov 15 |
Light frost vs. hard freeze
Average (50%) dates for each temperature. Tender plants are damaged at 36°F; most hardy crops survive until 28°F.
| Temperature | Last in spring | First in fall |
|---|---|---|
| Light frost (36°F) | Apr 17 | Oct 22 |
| Frost / freeze (32°F) | Apr 5 | Oct 30 |
| Hard freeze (28°F) | Mar 27 | Nov 9 |
Planting calendar for Stillwater
Transplant Apr 12 – Apr 26
Transplant Apr 19 – May 3
Transplant Apr 19 – May 3
Transplant Apr 12 – Apr 26
Sow or transplant Apr 12 – Apr 26
Sow or transplant Apr 12 – Apr 26
Sow or transplant Apr 19 – May 3
Sow or transplant Mar 8 – Mar 22
Fall sowing Sep 4 – Oct 2
Fall sowing Sep 4 – Sep 25
Fall sowing Aug 21 – Sep 4
Sow or transplant Mar 8 – Mar 22
Fall sowing Aug 21 – Sep 18
Transplant Mar 22 – Apr 5
Fall sowing Aug 7 – Aug 21
Transplant Mar 15 – Mar 29
Fall sowing Aug 7 – Aug 21
Fall sowing Aug 7 – Aug 21
Fall sowing Sep 18 – Oct 9
Fall sowing Aug 21 – Sep 4
Plant Mar 8 – Mar 22
Based on the average last frost (Apr 5) and first frost (Oct 30). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.