The best Asian greens for Alaska are the quick, loose-leaf, cool-season types: mizuna, tatsoi, komatsuna, baby pak choi and mustard greens. They finish within a short season, take light frost in stride and like cool nights. Heading napa cabbage is a gamble. Heat-lovers like water spinach have no chance. Variety choice matters, but sowing time matters just as much, because long summer days push many of these crops to bolt.
The short answer for Alaska
Choose by type, not by seed-packet name. Fast leafy greens go first, bolt-resistant pak choi second, and anything that needs a long, warm run comes last or stays off the list. The reference station in Anchorage has about 143 frost-free days between the mean last spring frost (May 3 to May 12) and the mean first fall frost (September 22 to October 1). Those dates come from NOAA’s 1991-2020 climate normals and mark the band where the chance of a 32F freeze runs between 30 and 70 percent. Anchorage is one of the mildest inhabited parts of the state. The Interior and the north have far shorter seasons.
Which Asian greens suit a short Alaska season?
Mizuna, tatsoi, komatsuna and baby-size pak choi are the dependable core. They are harvested young, often as cut-and-come-again leaves, so they do not need a full season to pay off. They also germinate in cool soil and handle the frosty nights that bracket the Alaska growing season on both ends. Mustard greens such as the red and frilly types belong here too, and their sharp flavor holds up well in cool weather.
Tokyo bekana and similar loose-heading leaf types are a good fourth choice. They give a milder, lettuce-like leaf and cope with variable weather better than some pak choi.
Which ones are worth a gamble?
Choy sum and gai lan (Chinese broccoli) can work, especially in a sheltered bed, but they flower quickly under long days. Treat the flower shoots as the crop rather than waiting for something bigger. Napa cabbage needs time to form a tight head and cool temperatures to do it, which is a hard combination when spring is late and summer days are endless. Sown for a late-summer harvest, it has a better chance, particularly under cover.
| Type | Fit for Alaska | Main reason |
|---|---|---|
| Mizuna, tatsoi, komatsuna | Best | Quick, cold-tolerant, harvested young |
| Baby pak choi, bekana | Very good | Small size, but choose bolt-resistant seed |
| Mustard greens | Very good | Handle cool nights and light frost |
| Choy sum, gai lan | Fair | Bolt quickly under long days |
| Napa cabbage | Risky | Needs time and cool weather to form a head |
| Water spinach, amaranth, Malabar spinach | Poor | Need real summer heat |
For sowing dates by region and week, see When to Sow Asian Greens in Alaska. For the broader picture of the crop in the state, Growing Asian Greens in Alaska covers beds, soil and care.
What will not work here
Heat-loving greens fail first. Water spinach, Malabar spinach and the leafy amaranths called callaloo in some kitchens sulk through cool nights and stop growing when soil stays cold. Even in Anchorage, where the season is long by Alaska standards, there is not enough warmth to carry them. Elsewhere in the state it is worse.
Why do spring sowings bolt in Alaska?
Many Asian greens treat long days as a signal to flower. Alaska’s summer daylight is long enough that a plant can read the whole season as a signal to go to seed. Mizuna and pak choi sown in late spring often bolt before they reach a decent size. The long daylight helps growth, which is why the plants grow fast, but it also shortens the harvest window. Bolt-resistant seed, shade cloth or a light-blocking cover for part of the day, and succession sowing in small batches all help. So does cutting young.
Which Asian greens do not make it through the season?
Anything slow. Full-size napa cabbage heads, large pak choi varieties bred for long seasons and root crops like big daikon all depend on weeks of steady warmth that a late May start and a first fall frost around the end of September rarely supply. Choose the quick, small-format version of the crop and finish it before cold nights arrive.
Winter is the other wall. The mean daily minimum of the coldest month at Anchorage is 11.0F. Asian greens are grown as annuals here and will not overwinter in an open bed. A cold frame or unheated greenhouse can extend the harvest at both ends of the season, but it will not carry plants through January.
Cold, wet spring soil is the practical problem. Seeds sown too early into cold soil rot or sit idle. Row cover laid right after sowing warms the soil a little, which gives the young plants a head start.
What changes across Alaska
The state is not one garden. The USDA Plant Hardiness Zone Map (2023, based on 1991-2020 data) runs from zone 1a to 8a across Alaska. That is a spread of many zones, so no single answer is right for the whole state. The zone is built on one variable, the average annual extreme minimum temperature, and says how cold it gets in winter. For annual greens, the length of the frost-free season and the summer’s daylight matter more than the winter minimum. Still, the zone spread shows how different one gardener’s conditions can be from another’s.
What should a gardener in the Interior or far north change?
The frost-free season shrinks the farther north and inland you go. Anchorage’s 143 frost-free days are a ceiling that many gardens do not reach. Pick only the fastest types, such as tatsoi, mizuna and mustard greens, and think in terms of one or two quick sowings rather than a long run. Start under cover, use row cover or a low tunnel, and harvest as baby leaves. At altitude, nights stay cold later into the season, so soil takes longer to warm and the first fall frost can arrive earlier than the Anchorage dates suggest. Push the start date back and have frost protection ready for the end.
What about coastal and southern gardens?
Coastal areas tend to have milder winters and a longer window before the first hard frost, but the summers are cool and often wet. The risks shift toward slugs, damp foliage and slow growth. Space plants a little wider than you would for a dry-summer garden so leaves dry between rains. Heat-lovers do no better here than inland. The tender, quick types still lead.
Gardeners wanting to know where their own yard sits can look up their location on the USDA Plant Hardiness Zone Map. Look at neighbors’ gardens too, since a slope, a south wall or a low pocket where cold air settles can change conditions a lot within a few hundred feet.
Where to check this for your own county
The state-level answer is only the start. The University of Alaska Fairbanks Cooperative Extension Service is the place to go next. It has district offices around the state and staff who know local conditions in their areas, from the Mat-Su Valley to the Kenai Peninsula to the Interior.
On the extension site, look for two things. The first is a local planting calendar or a vegetable-growing guide that gives sowing dates for your area. The second is any list of varieties trialled in your county or nearby. Trial results show which cultivars of pak choi, mizuna or mustard actually held up under local conditions, and that is more useful than a seed catalog description.
A county recommendation beats a state one. A state-level answer has to cover places with very different seasons, and so it works as a starting point. The local office can tell you which frost dates apply in your valley, whether root maggots are a problem in your area and which seed sources have worked for other gardeners nearby.
If a call or visit is possible, ask what has worked in the last couple of seasons. Local gardeners and Master Gardener volunteers tied to extension offices often keep that kind of knowledge, and it changes from year to year in ways printed guides cannot follow.
Checking this against your own garden
Dates on a calendar are averages. Your own bed tells you more, and three observations are worth making every spring.
- Soil warmth by feel. Dig a handful from the bed. If the soil feels cold to the touch, it is too early for most seeds. Soil that crumbles in your hand and feels cool but not icy is ready for the hardy greens.
- Leaf-out in the wild. Watch birch and willow near your yard, or when the first dandelions bloom. When they leaf out or flower, the season has turned, and your own spot may run earlier or later than the nearest weather station by days.
- First true leaves. After the seed leaves, the first true leaves show how the seedlings are coping. Strong, evenly colored growth means the site suits them. Purple tinges or stalled growth point to cold soil or a cold pocket, and a flower stalk rising before the plant has size points to bolting.
Write down what you see and the dates. After two or three seasons, those notes will tell you more about your microclimate than any chart.
Common questions
What is the easiest Asian green to grow in Alaska?
Tatsoi and mizuna are the easiest starting points. They germinate in cool soil, grow quickly and can be harvested young. Mustard greens are a close third.
Can I grow napa cabbage in Alaska?
It is possible but unreliable. Napa needs time and cool weather to form a head, and long summer days can push it to bolt. A late-summer sowing under row cover gives it a better chance than a spring one.
Will Asian greens survive an Alaska winter?
No. With a mean daily minimum of 11.0F in the coldest month at Anchorage, they will not overwinter in an open bed. A cold frame or unheated greenhouse can extend the harvest into fall and start it earlier in spring.
How do I stop Asian greens from bolting?
Choose bolt-resistant seed, sow small batches and harvest young. Shading the bed for part of the long day can also delay flowering. Cutting leaves early keeps plants producing longer.