What to plant in August in Wyoming
In Wyoming (WY), August sits about 4 weeks before the average first fall frost (September 15). The state averages 118 frost-free days a year (last frost May 20, first frost September 15; USDA zones 3a, 3b, 4a, 4b, 5a, 6a).
8 crops have a sowing or planting window this month, including chervil, mustard greens, spinach, tatsoi, turnip, arugula - and 7 of those windows close during August.
Dates here come from Wyoming frost dates (last frost May 20, first frost Sep 15). For one crop in detail, see when to plant spinach, arugula or radish in Wyoming.
Wyoming covers a very wide range of climates, so dates near you can be two weeks or more either side of these. Enter your ZIP code in the planting calendar for dates tuned to your town.
Wyoming: planting activity through the year
Last chance in August
Chervil (sow for a fall crop, by Aug 4) · Mustard Greens (sow for a fall crop, by Aug 4) · Spinach (sow for a fall crop, by Aug 4) · Tatsoi (sow for a fall crop, by Aug 4) · Turnip (sow for a fall crop, by Aug 4) · Arugula (sow for a fall crop, by Aug 11) · Watercress (sow for a fall crop, by Aug 11)
For fall and winter harvests (8)
Sowings counted back from Wyoming's first fall frost, so the crop matures before the cold - or, for garlic and similar, planted after it.
| Crop | What to do | Window | This month |
|---|---|---|---|
| Chervil | Sow for a fall crop | Jul 18 – Aug 4 | Last chance - ends Aug 4 |
| Mustard Greens | Sow for a fall crop | Jul 18 – Aug 4 | Last chance - ends Aug 4 |
| Spinach | Sow for a fall crop | Jul 18 – Aug 4 | Last chance - ends Aug 4 |
| Tatsoi | Sow for a fall crop | Jul 18 – Aug 4 | Last chance - ends Aug 4 |
| Turnip | Sow for a fall crop | Jul 18 – Aug 4 | Last chance - ends Aug 4 |
| Arugula | Sow for a fall crop | Jul 25 – Aug 11 | Last chance - ends Aug 11 |
| Watercress | Sow for a fall crop | Jul 25 – Aug 11 | Last chance - ends Aug 11 |
| Radish | Sow for a fall crop | Aug 1 – Aug 18 | Aug 1 – Aug 18 |
Harvesting in August
First harvests expected this month from crops sown or planted on time earlier in the season.
Planting dates for popular crops in Wyoming
Every crop has its own full-year dates for Wyoming: indoor start, transplant or direct sowing, and harvest.
Fall garden season: August garden jobs in Wyoming
- The average first frost is September 15, about 4 weeks away. Pick tender crops (tomatoes, peppers, squash, beans) before it, or cover them on cold nights.
- Still time to sow or plant: chervil, mustard greens, spinach, tatsoi, turnip, arugula. Fast greens and radishes are the safest bets this late.
- Row cover buys 4-6°F of frost protection and weeks of extra harvest - see season extension.
- Pull finished crops and sow a cover crop (cereal rye or crimson clover) into empty beds before the soil gets cold.
USDA zone chart for Wyoming
Wyoming spans USDA zones 3a, 3b, 4a, 4b, 5a, 6a. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average.
Questions gardeners ask
What vegetables can I plant in Wyoming in August?
8 crops have a window in August: chervil, mustard greens, spinach, tatsoi, turnip, arugula, watercress, radish. The tables above give the exact dates for each.
Is it too late to plant garlic in Wyoming in August?
Not too late - it's actually a little early. In Wyoming the next garlic window opens around September 26: plant in fall, after first frost.
Is it too late to plant tomatoes in Wyoming in August?
For this year, yes - the tomato windows in Wyoming have closed. The next step is to start seeds indoors from about March 25.
When is the first frost in Wyoming?
The statewide average first fall frost is around September 15 and the last spring frost around May 20. Wyoming covers a wide range of climates, so local dates can differ by two weeks or more - look yours up by ZIP code.
What can I harvest in Wyoming in August?
From plantings made on time: cabbage, basil, cauliflower, radicchio, tarragon, potato, parsley, new zealand spinach, fennel (bulb), summer savory.
What to plant in August in other states
Dates are computed from Wyoming’s statewide average frost dates (from NOAA/NCEI climate normals) and each crop’s timing in our crop database. Your garden may be a week or two either side - for dates tuned to your ZIP code, use the planting calendar.