Frost Dates for Tinley Park, IL
In Tinley Park, IL, the average last spring frost is around Apr 23 and the average first fall frost around Oct 20, for a growing season of about 179 days. For frost-tender plants, wait until May 11, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Park Forest, IL weather station, 8 miles away, elevation 710 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% | May 11 | Oct 6 |
| 20% | May 5 | Oct 12 |
| 30% | Apr 30 | Oct 15 |
| 40% | Apr 27 | Oct 18 |
| 50% | Apr 23 | Oct 20 |
| 60% | Apr 20 | Oct 23 |
| 70% | Apr 18 | Oct 25 |
| 80% | Apr 14 | Oct 28 |
| 90% | Apr 9 | Nov 1 |
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) | May 5 | Oct 10 |
| Frost / freeze (32°F) | Apr 23 | Oct 20 |
| Hard freeze (28°F) | Apr 12 | Oct 30 |
Planting calendar for Tinley Park
Transplant Apr 30 – May 14
Transplant May 7 – May 21
Transplant May 7 – May 21
Transplant Apr 30 – May 14
Sow or transplant Apr 30 – May 14
Sow or transplant Apr 30 – May 14
Sow or transplant May 7 – May 21
Sow or transplant Mar 26 – Apr 9
Fall sowing Aug 25 – Sep 22
Fall sowing Aug 25 – Sep 15
Fall sowing Aug 11 – Aug 25
Sow or transplant Mar 26 – Apr 9
Fall sowing Aug 11 – Sep 8
Transplant Apr 9 – Apr 23
Fall sowing Jul 28 – Aug 11
Transplant Apr 2 – Apr 16
Fall sowing Jul 28 – Aug 11
Fall sowing Jul 28 – Aug 11
Fall sowing Sep 8 – Sep 29
Fall sowing Aug 11 – Aug 25
Plant Mar 26 – Apr 9
Based on the average last frost (Apr 23) and first frost (Oct 20). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.