When to Plant Scallions in Wyoming (2026 Guide)

Growing scallions in Wyoming can be a rewarding experience, especially given their adaptability to various climates. With the median last spring frost falling on May 12 for Zone 5b, and on May 27 for Zone 5a, gardeners should plan their planting accordingly to ensure a bountiful harvest. This unique cool-season crop allows for flexible planting schedules, making it an excellent choice for gardeners looking to optimize their yields.

Wyoming's growing conditions foster robust scallion growth, as they thrive in cooler weather. Scallions can be direct-sown throughout the frost-free growing season, allowing for successive sowing at 3 to 4-week intervals. This strategy ensures an ongoing harvest from June through the fall, showcasing the versatility of scallions in almost any garden space, whether in rows or containers.

Harvesting scallions can begin as early as mid-June, leading into September, when the first fall frost is typically observed around September 19 in Zone 5a. Their ability to withstand light frosts, down to 28°F, provides a cushion for extending the harvest. By understanding frost dates and employing succession planting methods, Wyoming gardeners can enjoy a fresh supply of scallions well into the cool months.

Planting Schedule by USDA Zone in Wyoming

Zone	Indoor start	Transplant out	Direct sow	Harvest
Zone 5a	Start February 25 – March 1, ~6–8 weeks before May 27	Transplant outdoors June 1 – June 15, after the last frost	Direct sow from June 1 – August 15 for successive harvests	Harvest from June 15 – September 19, before the first fall frost
Zone 5b	Start February 15 – February 29, ~6–8 weeks before May 12	Transplant outdoors May 25 – June 10, just after the last frost	Direct sow from June 1 – August 30 for continuous crops	Harvest from June 10 – September 26, before the first fall frost

Scallions Planting Windows in Wyoming

Indoor start: Start seeds indoors from February 15 to February 29 for a successful early crop.
Transplant outdoors: Transplant scallion starts outdoors from May 25 to June 10 for optimal growth.
Harvest: Begin harvesting scallions in Wyoming from June 10 through September 26, before first fall frost.

Common Mistakes Growing Scallions in Wyoming

One common mistake among Wyoming gardeners is waiting too long to buy or start scallion seeds, often leading to missed planting opportunities due to late spring snow. Always check your local frost dates to align your planting schedules effectively.
Many gardeners underestimate how well scallions can handle light frost. In Wyoming, where temperatures can dip to 28°F, not using frost protection can result in damage. Be proactive with row covers during late-season frosts to ensure continued productivity.
Scallions planted in Wyoming's alkaline soils may struggle with nutrient uptake. Ensure your soil has enough organic matter and adjusted pH to maximize growth potential. Testing soil before planting can help avoid nutrient deficiencies.
Overcrowding scallions in small spaces is another misstep. While they can be grown in clusters, failing to thin them properly leads to competition for nutrients and light. Give each scallion plant enough space for root development to maximize yield.
Expecting to harvest scallions just once is a mistake. To maintain a steady supply in Wyoming's varying climate, gardeners should practice succession planting every 3 to 4 weeks. This ensures a reliable harvest, allowing for adjustments based on weather conditions.

Frequently Asked Questions

What if I'm in a cold pocket of Wyoming?

If you're in a colder microclimate, consider starting your seeds indoors and transplanting them only after the last frost date. Pay special attention to local weather patterns, and use protective measures like row covers to shield young plants from unexpected cold snaps.

Can I still plant scallions in May?

Yes, scallions can be planted throughout May, especially as the last frost date occurs around the middle of the month. Ensure that soil temperatures are adequate for germination, and consider starting in containers if you have limited garden space.

How often should I water my scallion crop?

Scallions require consistent moisture, particularly during dry spells. Water them gently whenever the soil feels dry about an inch down. Ensure good drainage to prevent root diseases caused by overly wet conditions.

What varieties of scallions do well in Wyoming?

Look for varieties that are bred for cooler climates or are specifically noted for good performance in shorter growing seasons. Varieties such as 'Evergreen Hardy' or 'Japanese Bunching' are popular choices for Wyoming gardens.

Can I regrow store-bought scallions?

Absolutely! After harvesting wine scallions, simply keep 1-2 inches of the base with roots intact. Replant in moist soil or water in a sunny window, and you'll have new green growth within days for a continual supply!