Frost Dates for Springfield, IL
In Springfield, IL, the average last spring frost is around Apr 15 and the average first fall frost around Oct 22, for a growing season of about 188 days. For frost-tender plants, wait until Apr 30, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Springfield #2, IL weather station, 2 miles away, elevation 599 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 30 | Oct 9 |
| 20% | Apr 24 | Oct 15 |
| 30% | Apr 20 | Oct 17 |
| 40% | Apr 18 | Oct 20 |
| 50% | Apr 15 | Oct 22 |
| 60% | Apr 12 | Oct 24 |
| 70% | Apr 10 | Oct 27 |
| 80% | Apr 7 | Oct 30 |
| 90% | Apr 3 | Nov 2 |
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 27 | Oct 13 |
| Frost / freeze (32°F) | Apr 15 | Oct 22 |
| Hard freeze (28°F) | Apr 5 | Nov 1 |
Planting calendar for Springfield
Transplant Apr 22 – May 6
Transplant Apr 29 – May 13
Transplant Apr 29 – May 13
Transplant Apr 22 – May 6
Sow or transplant Apr 22 – May 6
Sow or transplant Apr 22 – May 6
Sow or transplant Apr 29 – May 13
Sow or transplant Mar 18 – Apr 1
Fall sowing Aug 27 – Sep 24
Fall sowing Aug 27 – Sep 17
Fall sowing Aug 13 – Aug 27
Sow or transplant Mar 18 – Apr 1
Fall sowing Aug 13 – Sep 10
Transplant Apr 1 – Apr 15
Fall sowing Jul 30 – Aug 13
Transplant Mar 25 – Apr 8
Fall sowing Jul 30 – Aug 13
Fall sowing Jul 30 – Aug 13
Fall sowing Sep 10 – Oct 1
Fall sowing Aug 13 – Aug 27
Plant Mar 18 – Apr 1
Based on the average last frost (Apr 15) and first frost (Oct 22). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.