Frost dates for Indianapolis, IN
At Indianapolis, the median last spring frost (32°F) is Apr 15 and the median first fall frost is Oct 26, for a typical growing season of 193 days. For a 90% chance that the last frost has passed, wait until May 2. Nearby ZIP codes are in USDA hardiness zone 6b.
- Apr 15Last spring frost (median)50% chance of 32°F after this date
- May 2Safer planting date10% chance of 32°F after this date
- Oct 26First fall frost (median)50% chance of 32°F by this date
- 193 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | Apr 11 | Apr 26 | May 12 |
| 32°F | Apr 2 | Apr 15 | May 2 |
| 28°F | Mar 18 | Apr 4 | Apr 21 |
| 24°F | Mar 7 | Mar 24 | Apr 8 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Oct 5 | Oct 17 | Oct 28 |
| 32°F | Oct 13 | Oct 26 | Nov 7 |
| 28°F | Oct 24 | Nov 5 | Nov 21 |
| 24°F | Nov 2 | Nov 17 | Dec 4 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 151 days | 171 days | 191 days |
| 32°F | 171 days | 193 days | 212 days |
| 28°F | 195 days | 215 days | 236 days |
| 24°F | 218 days | 239 days | 262 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 46241 | 6b | -5 to 0°F | 3 km |
| 46221 | 6b | -5 to 0°F | 4 km |
| 46217 | 6b | -5 to 0°F | 8 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USW00093819, at 39.7075, -86.2803, elevation 241 m (790 ft).
- Data quality: Standard (24+ years of data), 29 years of freeze data.
- Average days per year at or below 32°F: 106.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Indianapolis Nwfo (0 km)
- Indianapolis Eagle Creek Airport (13 km)
- Indianapolis SE Side (18 km)
- Castleton 2 S (27 km)
- Whitestown (33 km)
- Franklin Wastewater Plant (34 km)
- Carmel 3 E (34 km)
- Jamestown 2 E (36 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.