Wyoming's vegetable gardening is defined by its short window: most of the state sits in USDA zones 4bโ6a, with last frost dates ranging from late May at elevation to early May in lower basins, and first fall frosts arriving as early as mid-August in some areas. That gives many gardeners just 90โ110 frost-free days โ barely enough for warm-season crops, but ideal territory for cool-season vegetables that actually perform better when nights stay cold.
The real challenge isn't cold per se โ it's the compressed shoulder seasons and the wind. Wyoming's high-altitude sun is intense, soils can be alkaline and lean, and late spring snowstorms are routine. Crops that germinate in cool soil, tolerate light frost, and mature before August heat or September cold closes the season are the ones that consistently produce.
The vegetables listed here were selected because they meet Wyoming's binding constraint: they either mature fast enough to fit the window, can be started indoors to extend it, or โ like garlic โ are planted in fall and overwinter under snow. Prioritize direct-sowing as soon as soil is workable in April, use row cover to push earlier starts, and lean on short-day or early-maturing varieties throughout.
At a glance
| Crop | Type | Days to harvest | Sun | Heat | Frost | Level |
|---|---|---|---|---|---|---|
| Pea | Cool | 55โ70 days | Full | โ | โ | Easy |
| Broccoli | Cool | 60โ90 days | Full | โ | โ | Moderate |
| Cabbage | Cool | 60โ100 days | Full | โ | โ | Moderate |
| Cauliflower | Cool | 60โ100 days | Full | โ | โ | Hard |
| Kale | Cool | 50โ65 days | Full | โ | โ | Easy |
| Lettuce | Cool | 30โ60 days | Part | โ | โ | Easy |
| Spinach | Cool | 35โ50 days | Part | โ | โ | Easy |
| Swiss chard | Cool | 50โ60 days | Full | โ | โ | Easy |
| Carrot | Cool | 60โ80 days | Full | โ | โ | Moderate |
| Beet | Cool | 50โ70 days | Full | โ | โ | Easy |
| Radish | Cool | 25โ35 days | Part | โ | โ | Easy |
| Onion | Cool | 90โ120 days | Full | โ | โ | Moderate |
| Garlic | Cool | 240โ270 days | Full | โ | โ | Easy |
| Strawberry | Cool | 90โ110 days | Full | โ | โ | Moderate |
Why each one works
Pea
Cool-season 55โ70 daysPeas are arguably Wyoming's most dependable crop: they germinate in soil as cold as 40ยฐF, tolerate frost down to the mid-20s, and finish in 55โ70 days โ well inside even the tightest Wyoming window. Direct-sow as soon as ground is workable in late March or April, as soon as soil temperature reaches 45ยฐF; heat stalls them, so early planting is essential. Choose 'Alaska' or 'Sugar Ann' for the fastest maturity.
Full pea growing guide โBroccoli
Cool-season 60โ90 daysBroccoli's 60โ90 day range fits Wyoming's season when started indoors 4โ6 weeks before last frost and transplanted out in May under row cover. Cool nights actually improve head quality and flavor; Wyoming's persistent cool temperatures prevent the premature bolting that plagues broccoli in warmer climates. 'Arcadia' and 'Belstar' are reliable performers with good cold tolerance.
Full broccoli growing guide โCabbage
Cool-season 60โ100 daysCabbage handles Wyoming's late frosts without flinching and can tolerate light snow on the head โ a practical advantage when fall arrives early. Start transplants indoors in March and set out in early May; a fall crop started in late June will mature into September's cool weather for the best flavor. 'Earliana' and 'Gonzales' suit the shorter end of the season.
Full cabbage growing guide โCauliflower
Cool-season 60โ100 daysCauliflower is the most temperature-sensitive crop on this list and Wyoming's brief warm window makes it genuinely challenging โ but achievable with indoor starts and careful timing. Transplant after last frost with row cover ready, and aim for head formation during cool weather rather than summer heat. Stick to fast-maturing varieties like 'Snow Crown' (50 days from transplant) to stay inside the frost window.
Full cauliflower growing guide โKale
Cool-season 50โ65 daysKale is one of Wyoming's most forgiving crops: it germinates in cold soil, tolerates hard frosts, and actually sweetens after a freeze as starches convert to sugars. Direct-sow in April or start transplants indoors in March; kale can be harvested from June through October and will often survive into November under light mulch. 'Winterbor' and 'Red Russian' both handle Wyoming conditions well.
Full kale growing guide โLettuce
Cool-season 30โ60 daysLettuce matures in as few as 30 days for loose-leaf types, making it one of the few crops Wyoming gardeners can succession-plant across the season. Sow outdoors from late April and again in late July for a fall harvest; use shade cloth in midsummer if temperatures consistently reach the mid-80s. Cut-and-come-again varieties like 'Black Seeded Simpson' or 'Salad Bowl' maximize yield from limited space.
Full lettuce growing guide โSpinach
Cool-season 35โ50 daysSpinach is Wyoming's earliest possible harvest โ it tolerates temperatures down to 20ยฐF and can be direct-sown as soon as soil is thawed in late March. At 35โ50 days, a second sowing in late July will produce into October under row cover. 'Tyee' and 'Bloomsdale Long Standing' resist bolting better than standard varieties when temperatures swing.
Full spinach growing guide โSwiss chard
Cool-season 50โ60 daysSwiss chard bridges Wyoming's cool spring and warm summer better than almost any other leafy green: it tolerates both frost and summer heat without bolting, and a single planting sown in May will produce continuously through fall. It germinates reliably in cool soil and needs no special attention once established. 'Fordhook Giant' is a proven variety; 'Rainbow' offers similar performance with colorful stems.
Full swiss chard growing guide โCarrot
Cool-season 60โ80 daysCarrots need 60โ80 days but tolerate light frost at both ends of the season, making them a reliable Wyoming root crop when sown in early May. The key challenge is germination in cold, crusted soil: cover the row with burlap or a board until sprouts emerge to retain moisture. 'Danvers 126' and 'Bolero' are well-suited to Wyoming's heavier, alkaline soils.
Full carrot growing guide โBeet
Cool-season 50โ70 daysBeets combine fast maturity (50โ70 days), frost tolerance, and heat resilience โ a useful combination for Wyoming's variable summers. Direct-sow in late April and thin aggressively to 3-inch spacing; the thinnings are edible greens. 'Detroit Dark Red' is a standard performer; 'Chioggia' matures slightly faster and handles temperature swings well.
Full beet growing guide โRadish
Cool-season 25โ35 daysAt 25โ35 days from seed to harvest, radishes are Wyoming's fastest return and work as both a crop and a soil-warming nurse plant for slower germinators sown alongside them. Sow directly in April and again every two weeks through May; summer heat causes pithiness and bolting, so pause midsummer and resume in August for a fall crop. 'Cherry Belle' and 'French Breakfast' are reliable for spring rounds.
Full radish growing guide โOnion
Cool-season 90โ120 daysOnions are the most season-length-demanding crop on this list at 90โ120 days, which means Wyoming gardeners must start transplants indoors in late January or buy sets โ direct-seeding outdoors won't work at most Wyoming elevations. Choose short-day or intermediate varieties suited to northern latitudes, like 'Walla Walla' or 'Copra', and plant out as soon as soil is workable in April. Sets of yellow storage onions are the simplest route for beginners.
Full onion growing guide โGarlic
Cool-season 240โ270 daysGarlic sidesteps Wyoming's short growing season entirely by being planted in fall (late September to mid-October), overwintering under snow, and harvesting in July โ the snow actually insulates the bulbs through the coldest months. Plant hardneck varieties like 'German Red' or 'Chesnok Red', which are specifically bred for cold-climate performance and produce large, flavorful cloves. Mulch 4โ6 inches deep after planting and remove mulch in spring as shoots emerge.
Full garlic growing guide โStrawberry
Cool-season 90โ110 daysStrawberries are perennial and, once established, survive Wyoming winters reliably under snow cover or a straw mulch applied after the ground freezes. June-bearing varieties like 'Honeoye' and 'Surecrop' are well-matched to Wyoming's climate and produce a concentrated harvest timed to the warmest weeks. Plant bare-root crowns in early May, remove flowers the first year to build root systems, and expect full production in year two.
Full strawberry growing guide โFrequently asked questions
When is the last frost date in Wyoming, and how should I plan around it?
Last frost dates vary significantly by location: Cheyenne averages May 11, Casper around May 18, and higher-elevation areas can see frost into early June. Use your specific county's historical frost data from the National Weather Service and plan transplant dates accordingly. Row cover adds roughly 4โ6ยฐF of protection and lets you push transplants out 2โ3 weeks earlier than bare-ground timing.
Can I grow any warm-season crops like tomatoes or squash in Wyoming?
Yes, but success requires starting transplants indoors 6โ8 weeks before last frost and using season-extension tools like wall-o-waters, row cover, or cold frames to gain extra weeks on both ends. Stick to the fastest-maturing varieties available โ 'Stupice' tomato (52 days) and 'Patio' pepper, for instance โ and choose sheltered, south-facing beds. At higher elevations above 7,000 feet, reliable tomato production is genuinely difficult even with extensions.
Should I amend Wyoming's alkaline soils before planting vegetables?
Most Wyoming soils are alkaline (pH 7.5โ8.5) and low in organic matter, which limits nutrient availability for vegetables that prefer pH 6.0โ7.0. Work in 3โ4 inches of compost before planting each season to lower pH incrementally and improve moisture retention. Sulfur amendments can lower pH more quickly but act slowly โ apply the fall before planting. Leafy greens and beets tolerate alkalinity better than carrots and onions, which may show yellowing in high-pH soils.
Is it worth using a cold frame or greenhouse in Wyoming?
Absolutely โ a cold frame or unheated hoop house extends the effective growing season by 4โ6 weeks on each end, which is transformative when your frost-free window is only 90โ100 days. Even a simple row cover tunnel over a raised bed lets you start peas in late March and harvest kale through November. Permanent cold frames oriented south with glazed tops are particularly useful for overwintering spinach and growing early spring lettuce before the main garden is workable.