When to Plant Scallions in Montana (2026 Guide)

Scallions, also known as green onions or bunching onions, are a fantastic crop option for Montana gardeners due to their adaptability and flavorful additions to meals. With a short growing season, it's essential to understand when to plant and how to make the most of your growing space. In Montana, you can effectively harvest scallions up until the median last frost date of June 5 in Zone 4b, allowing for a continuous supply of fresh greens on your table.

In regions like Billings, which falls within Zone 5b, the last spring frost typically occurs around May 8. This multifaceted crop can be grown intensively, allowing you to sow every 3 to 4 weeks for a steady harvest. Scallions thrive in cooler temperatures, providing an ideal crop to start early in the spring and throughout the cooler months of fall.

It's important to consider the specific frost dates related to the hardiness zone you are in. For instance, those within Zone 5a can expect their last frost around May 24, while gardeners in Zone 4b should plan for June 5. This information will significantly aid gardeners in scheduling their planting and ensuring they successfully grow scallions throughout the gardening season.

Planting Schedule by USDA Zone in Montana

Zone	Indoor start	Transplant out	Direct sow	Harvest
Zone 5a	Start March 15 – March 31, ~6 weeks before May 8	Transplant outdoors after May 8	Direct sow from May 9 – May 24	Harvest from June 24 – September 16
Zone 4b	Start March 15 – March 31, ~6 weeks before June 5	Transplant outdoors after June 5	Direct sow from June 6 – June 15	Harvest from July 15 – September 13
Zone 5b	Start March 1 – March 15, ~6 weeks before May 8	Transplant outdoors after May 8	Direct sow from May 9 – June 1	Harvest from June 24 – September 27

Scallions Planting Windows in Montana

Indoor start: For all zones, begin starting scallion seeds indoors from March 1 to March 31 to ensure a successful outdoor transplant.
Transplant outdoors: Transplant scallions outdoors based on your zone: after May 8 in Zone 5b and after June 5 in Zone 4b.
Harvest: The harvest window spans from late June to mid-September, with scallions ready to pick starting as early as June 24 in Zone 5a.

Common Mistakes Growing Scallions in Montana

One common mistake Montana gardeners make is starting seeds too late in the spring. With the fluctuating weather, it's crucial to reference the last frost dates to ensure your scallions have the best start possible.
Assuming that scallions won’t tolerate cold is another pitfall. Many Montana gardeners overlook their resilience to frost. They can withstand light frosts, so don’t be afraid to plant a bit earlier in the season.
Another error is planting scallions too far apart. Due to their ability to grow densely in clusters, planting them too sparsely limits your yield. Maximizing space is key, especially in smaller Montana gardens.
Using heavy soil without proper amendments can hinder scallion growth. Montana gardeners often overlook the importance of soil composition and drainage, which can significantly impact the health of their crops.
Waiting too long to harvest is a mistake many make. Montana's growing season can be short; scallions can be picked early for their best flavor and should not be left to overgrow, particularly as frost approaches.

Frequently Asked Questions

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

In colder pockets, be attentive to local frost dates that may be delayed. You may need to adjust your planting schedule to account for later frost occurrences, starting seeds indoors or using protective measures.

Can I still plant scallions in May?

Yes, scallions can be planted in May after the last frost date has passed. In many regions of Montana, such as Billings, mid-May is an excellent time to start sowing directly outdoors.

How much sunlight do scallions need?

Scallions require at least 6 hours of sunlight each day to thrive. Full sun exposure leads to stronger plants and better flavor, so make sure to choose a sunny spot in your garden.

When is the best time to harvest scallions?

Scallions can be harvested as soon as they reach the desired size, typically around 60 to 70 days after planting. Late June to early July is ideal for the first harvest in most of Montana, extending into September.

Can scallions be grown in containers?

Yes, scallions are excellent for container gardening! Use pots that are at least 6 inches deep and ensure they receive plenty of sunlight. This way, you can grow scallions even in smaller spaces.