When to plant potatoes in Wyoming
Wyoming’s average last spring frost is May 20, and the first fall frost typically arrives around September 15 — about 118 frost-free days (USDA zones 3a, 3b, 4a, 4b, 5a, 6a). Potato needs 70–120 days to mature, which fits comfortably within Wyoming's growing season.
Wyoming covers a wide range of climates, so your exact frost dates may differ from the state average by two weeks or more. For dates tuned to your town, use the calendar generator.
When to plant potatoes in Wyoming: the short answer
For a spring planting, sow May 1 – May 20. Seeds germinate in soil from 45 to 80°F.
Windows are ~1–2 week bands around each date. Frost dates are a statewide average from NOAA/NCEI normals; your town may differ by two weeks or more. Calendar year 2026.
How to grow potatoes in Wyoming, step by step
- Prepare the bed. They need at least six to eight hours of direct sun a day and loose soil at least 18 inches deep, with a pH between 4.8 and 6.5. Dig in compost before planting.
- Sow outdoors (May 1 – May 20). Space plants about 12 inches apart in rows 32 inches apart, sowing seed 4 inches deep. It tolerates a light frost but not a hard freeze. As a cool-season crop it does best before summer heat arrives in Wyoming.
- Water and feed. Give it steady, even moisture, about an inch of water a week from rain or the hose.
- Watch for pests and problems. Pests: Colorado potato beetle, flea beetle, wireworm, aphids. Diseases and disorders: late blight, early blight, common scab, blackleg.
- Harvest (from about Jul 15 – Sep 3). Potato takes 70-120 days to reach harvest. Plant certified seed potatoes, not grocery-store ones. Hill soil or mulch over the stems as they grow to stop greening. New potatoes ~10 weeks in; storage potatoes after the tops die back.
Figures come from our crop data; dates use Wyoming’s average frost dates. More in the full potato growing guide.
Potato planting dates by USDA zone in 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, so the potato dates shift with them.
When to plant potatoes in nearby states
Questions gardeners in Wyoming ask
When is the best time to plant potatoes in Wyoming?
Sow potatoes in Wyoming between May 1 and May 20. That timing is set by Wyoming's average last spring frost of May 20; Wyoming spans several climates, so cooler and higher parts of the state run later.
When will potatoes planted in Wyoming be ready to harvest?
Planted on time, potatoes are usually ready from about July 15 to September 3, 70-120 days after sowing.
When is the last frost in Wyoming?
On average around May 20, with the first fall frost around September 15 - about 118 frost-free days. Your town may differ by two weeks or more.