Frost dates · USDA zone 5b
Frost dates for Cheyenne, WY
Cheyenne, WY sees its last 32 °F night of spring around May 14 and its first of fall around October 1 — a 139-day freeze-free season in a typical year.
Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.
Freeze odds, by date
| Odds | Last spring freeze after | First fall freeze before |
|---|---|---|
| 9 years in 10 | May 3 | Oct 14 |
| Median — 1 year in 2 | May 14 | Oct 1 |
| 1 year in 10 | May 28 | Sep 17 |
The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 139 days median, at least 119 in 9 years of 10, at least 155 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of May 3 and first of Oct 10.
Cheyenne planting calendar, 2027
Every row runs from the median last frost (May 14) and median first frost (Oct 1) above, using each cultivar's days to maturity. Same engine as the Plan Builder.
| Crop | Start indoors | Transplant / plant | First harvest | Days |
|---|---|---|---|---|
| Hardneck GarlicSiberian (porcelain hardneck) | — | Oct 15prior fall | Jun 12 | 240 from sow |
| Spanish OnionYellow Sweet Spanish (long-day) | Feb 19 | Apr 16 | Aug 4 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | May 14 | Jun 13 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Apr 30 | Apr 30 | Jun 14 | 45 from sow |
| Genovese BasilGenovese | Apr 16 | May 28 | Jul 27 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Mar 19 | May 21 | Aug 4 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Mar 5 | May 28 | Aug 31 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Mar 19 | May 21 | Aug 4 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Mar 19 | May 21 | Aug 9 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Mar 19 | May 21 | Aug 9 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Apr 30 | Apr 30 | Jul 9 | 70 from sow |
| TomatilloToma Verde | Apr 2 | May 21 | Jul 30 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Apr 2 | May 21 | Aug 4 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Apr 2 | May 21 | Aug 9 | 80 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.
What sauce can Cheyenne grow?
Each sauce, scheduled for a Cheyenne container garden: when the first seeds go in and when enough fruit has ripened for one batch.
Cheyenne frost questions
When is the last frost in Cheyenne, WY?
The median last 32 °F freeze at CHEYENNE WFO, WY is May 14: half of years see a later one. One year in ten, a freeze still comes after May 28; nine years in ten, it comes after May 3. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in Cheyenne, WY?
The median first 32 °F freeze of fall is October 1. One year in ten it arrives before September 17; nine years in ten, before October 14.
How long is the growing season in Cheyenne, WY?
139 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 119 days; one year in ten, at least 155 days.
What growing zone is Cheyenne, WY?
USDA hardiness zone 5b, per the 2023 USDA Plant Hardiness Zone Map for ZIP 82005. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.
When should I plant tomatoes in Cheyenne, WY?
Start Roma VF (determinate paste) seeds indoors around Apr 2 and transplant around May 21, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for May 28. First ripe fruit lands around Aug 4.
When should I plant peppers in Cheyenne, WY?
Sow jalapeño indoors on a heat mat around Mar 19; transplant no earlier than May 21, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Aug 4.
Nearby in Wyoming
- Casperlast frost May 10
All Wyoming frost dates → · How frost-date math drives a sowing calendar →