Glossary /
Growing season
The growing season is the span between the last spring freeze and the first fall freeze — the window in which frost-sensitive plants can live outdoors. NOAA computes it per station from 30 years of data; we aggregate every station inside each zone. It ranges from under 120 days in zone 3 to effectively year-round in zones 9 and warmer, which is why the same vegetable is a spring crop in Duluth and a winter crop in Tampa.
Growing season by zone (median days at 32°F, NOAA 1991–2020)
| Zone | Days |
|---|---|
| 3a | — |
| 3b | — |
| 4a | — |
| 4b | — |
| 5a | — |
| 5b | — |
| 6a | — |
| 6b | — |
| 7a | — |
| 7b | — |
| 8a | — |
| 8b | — |
| 9a | — |
| 9b | — |
| 10a | — |
| 10b | — |
| 11a | — |
See also: Last frost date · First frost date