Zone 14 May 21 - May 31 | Zone 15 Jun. 1 - Jun. 10 | Zone 16 Jun. 11 - Jun. 20 | Zone 17 Jun. 21 - Jun. 30 |
Zone 18 Jul. 1 - Jul. 10 | Zone 19 Jul. 11 - Jul. 20 | Zone 20 Jul. 21 - Jul. 31 | Zone 21 Frost Year Round |
Plantmaps has derived zones indicating the Interactive map of average annual Last frost dates for the state of Wyoming