Last frost date in Rock Springs, Wyoming
May 24
Average last frost in spring. In an early year (1 in 10) it's over by May 8; in a late year (1 in 10) it comes after June 9.
September 24
Average first frost in fall. 1 year in 10 it comes by September 9.
Source: NOAA U.S. Climate Normals 1991–2020, station Rock Springs Fire Dept (USC00487847), 1.5 miles from Rock Springs, elevation 6,270 ft. NOAA National Centers for Environmental Information. These are long-term averages, not a forecast.
| Early year | Average | Late year | |
|---|---|---|---|
| Last frost in spring | May 8 | May 24 | June 9 |
| First frost in fall | Sept 9 | Sept 24 | Oct 4 |
An early or late year is one in 10: 1 year in 10 the frost comes before the early date, and 1 year in 10 after the late date.
Frost-free days in an average year: 121
Planting calendar for Rock Springs
Fall planting
USDA dates for places whose average first freeze is about September 20 (Rock Springs: September 24).
- Broccoli plantsMay 1 – June 15 (past for this year)
- Brussels sprouts plantsMay 1 – June 15 (past for this year)
- Cabbage plantsMay 1 – June 15 (past for this year)
- Cantaloupe (muskmelon)May 1 – June 15 (past for this year)
- Cauliflower plantsMay 1 – July 1 (past for this year)
- PotatoesMay 1 – June 15 (past for this year)
- WatermelonMay 1 – June 15 (past for this year)
- Celery and celeriac plantsMay 15 – July 1 (past for this year)
- Chervil and chivesMay 15 – June 15 (past for this year)
- Collards plantsMay 15 – June 15 (past for this year)
- ParsnipsMay 15 – June 15 (past for this year)
- Summer squashMay 15 – July 1 (past for this year)
- Witloof chicoryMay 15 – June 15 (past for this year)
- SalsifyMay 20 – June 20 (past for this year)
- Winter squashMay 20 – June 10 (past for this year)
- BeetsJune 1 – July 1 (past for this year)
- CarrotsJune 1 – July 1 (past for this year)
- Chinese cabbageJune 1 – July 1 (past for this year)
- CucumbersJune 1 – 15 (past for this year)
- DandelionJune 1 – July 1 (past for this year)
- Florence fennelJune 1 – July 1 (past for this year)
- Garden peasJune 1 – July 15 (past for this year)
- Head lettuce plantsJune 1 – July 15 (past for this year)
- KaleJune 1 – July 1 (past for this year)
- KohlrabiJune 1 – July 15 (past for this year)
- Leaf lettuceJune 1 – Aug 1 (past for this year)
- Mustard greensJune 1 – Aug 1 (past for this year)
- OkraJune 1 – 20 (past for this year)
- ParsleyJune 1 – July 1 (past for this year)
- Peppers plantsJune 1 – 20 (past for this year)
- RadishesJune 1 – Aug 15 (past for this year)
- RutabagaJune 1 – July 1 (past for this year)
- Snap beansJune 1 – July 1 (past for this year)
- SorrelJune 1 – July 1 (past for this year)
- SpinachJune 1 – Aug 1 (past for this year)
- Sweet cornJune 1 – July 1 (past for this year)
- Swiss chardJune 1 – July 1 (past for this year)
- TomatoesJune 1 – 20 (past for this year)
- TurnipsJune 1 – July 15 (past for this year)
- Corn saladJune 15 – Aug 1 (past for this year)
- EndiveJune 15 – July 15 (past for this year)
- Upland cressJune 15 – Aug 1 (past for this year)
- Rhubarb plantsSept 15 – Nov 1Now
USDA lists garlic, horseradish, leeks, onion plants, onion seed, onion sets, shallots as generally spring-planted here.
Spring planting
USDA dates for places whose average last freeze is about May 20 (Rock Springs: May 24).
- SpinachApr 10 – June 15
- Chervil and chivesApr 15 – May 15
- Corn saladApr 15 – June 1
- DandelionApr 15 – May 15
- Garden peasApr 15 – June 1
- GarlicApr 15 – May 15
- PotatoesApr 15 – June 15
- RadishesApr 15 – June 15
- Rhubarb plantsApr 15 – May 10
- TurnipsApr 15 – June 1
- Asparagus plantsApr 20 – May 15
- Horseradish plantsApr 20 – May 20
- KaleApr 20 – May 10
- KohlrabiApr 20 – May 20
- Onion plants plantsApr 20 – May 15
- Onion seedApr 20 – May 15
- Onion setsApr 20 – May 15
- ShallotsApr 20 – May 10
- BeetsApr 25 – June 15
- Broccoli plantsMay 1 – June 15
- Brussels sprouts plantsMay 1 – June 15
- Cabbage plantsMay 1 – June 15
- CarrotsMay 1 – June 1
- Chinese cabbageMay 1 – June 15
- Collards plantsMay 1 – June 1
- EndiveMay 1 – 30
- Florence fennelMay 1 – 30
- Head lettuce plantsMay 1 – June 30
- Leaf lettuceMay 1 – June 30
- LeeksMay 1 – 20
- Mustard greensMay 1 – June 30
- ParsleyMay 1 – 20
- ParsnipsMay 1 – 20
- RutabagaMay 1 – 20
- SalsifyMay 1 – June 1
- SorrelMay 1 – June 1
- Upland cressMay 1 – June 1
- Cauliflower plantsMay 10 – June 15
- Celery and celeriac plantsMay 10 – June 15
- Swiss chardMay 10 – June 15
- Snap beansMay 15 – June 30
- Sweet cornMay 15 – June 1
- New Zealand spinachMay 20 – June 15
- Summer squashMay 20 – June 15
- Peppers plantsMay 25 – June 15
- TomatoesMay 25 – June 15
- CucumbersJune 1 – 15
- Eggplant plantsJune 1 – 15
- OkraJune 1 – 20
- Witloof chicoryJune 1 – 15
- WatermelonJune 15 – July 1
Planting dates: USDA Home and Garden Bulletin No. 9 (1967), “Suburban and Farm Vegetable Gardens,” tables 4 and 5 (earliest safe spring and latest safe fall dates), applied to this place's NOAA frost dates. “Plants” means setting out transplants, not sowing seed. How we match the table.
Nearby in Wyoming
- Green River 14 mi · last frost May 24
- Evanston 93 mi · last frost June 12
- Riverton 108 mi · last frost May 12
- Jackson 152 mi · last frost June 20
- Casper 172 mi · last frost May 10