Vegetable · Brassicaceae
Mizuna
Brassica rapa var. nipposinica
Sow it in cool weather, keep it watered, and cut it often, and mizuna will keep feeding you for weeks.
Full sun
Every 2–4 days
39–75°F · 4–24°C
20–45 days
Overview
Mizuna is a friendly Japanese mustard green with feathery, deeply cut leaves and a mild peppery taste that sits somewhere between arugula and a young mustard leaf. It is part of the cabbage family and it grows quickly, taking only about three weeks from seed to a first cutting. You can enjoy it raw in a salad or stir it into soups and stir-fries right at the end of cooking.
The nicest thing about mizuna is how forgiving it is, which makes it a wonderful choice if you are just finding your feet. It is a cool-season green that takes light frost calmly, comes back after each cutting, and asks for little beyond steady moisture. Its one soft spot is heat, since hot, long days coax it into flowering and turn the leaves bitter, and even that is easy to work around.
Grow it as a cut-and-come-again green and a single sowing will keep giving for weeks, so you get plenty of reward for very little worry. Sow in early spring and again in late summer, take the outer leaves whenever you want them, and the plant kindly sends up fresh growth from the center.
Care
The short version: give mizuna full sun to part shade in cool weather, keep the soil evenly moist, plant it in rich, well-drained ground, and cut the leaves often so fresh ones keep coming, and you can hardly go wrong.
Light
Mizuna is happiest in full sun, around 6 or more hours a day, yet it takes partial shade with no fuss at all. When the weather warms up that touch of afternoon shade becomes a real friend, since it slows the bolting that heat tends to bring on.
Water
Keep the soil evenly moist and the leaves come in fast and tender, which is exactly what you want. It will manage on leaner soil with less water, but the flavor and quality slip a little, so aim to water every 2 to 4 days. That steady moisture is what keeps the greens mild and sweet rather than sharp.
Soil
Give it well-drained ground rich in organic matter, with a good helping of compost mixed in, and it will settle in nicely. A pH between 6.0 and 7.0 suits it well, and happily that covers most garden soils without any special effort.
Temperature
Mizuna loves cool weather and is happiest from about 39°F to 75°F (4°C to 24°C). It shrugs off light frost down at the low end, while heat up near the top nudges it to flower and lose its sweetness, so a cool spot is a real help.
Humidity
Ordinary humidity, somewhere around 40% to 70%, is all it asks, so there is truly no number to chase outdoors. Good airflow matters more than the reading, since crowded, damp leaves are what invite pests and rot.
Feeding
Mix aged compost or a balanced, nitrogen-rich feed into the bed before you sow, then feed monthly through the growing season. The nitrogen fuels the leafy growth you are after, though go gently, since soft, overfed growth is the kind aphids come looking for.
Pruning
Here the harvesting is the pruning, which keeps things simple. Cut the leaves about 2 inches (5 cm) above the crown or take the outer leaves one at a time, and the plant regrows for cutting after cutting. That kind cut-and-come-again habit is what lets a single sowing carry on for weeks.
Size & spacing
These are tidy little plants, reaching 8 to 18 inches (20 to 45 cm) tall and about as wide. Give each one room to fill its 10 to 18 inch (25 to 45 cm) spread so air can move through and the leaves stay clean and healthy.
When to plant
Mizuna is happiest at the cool edges of the year rather than the heat of high summer, so there is an easy rhythm to follow. Sow it in early spring as soon as you can work the soil, then sow again in late summer for a fall crop. It takes light frost in stride, which lets the season carry on well past the first chilly nights.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: 4-6 weeks before last spring frost, or direct sow
- Plant: early spring and again in late summer; cool-season and frost-tolerant
- Harvest: baby leaves about 21 days, full leaves about 40 days; cut-and-come-again
Hardiness
USDA hardiness zones: 4–9
Temperature: down to -34°C
Troubleshooting
Most of the little troubles mizuna runs into come down to a handful of brassica pests and the heat that makes it bolt, and none of them are the end of the crop. Spot the early signs on the leaves and you can usually head things off before they matter. Match what you see below and act while it still does some good.
Young plants flopping over as the roots give way
When a seedling wilts and no dry soil explains it, gently lift one and look for white grubs and tunneled roots, the sign of the cabbage maggot. Pull and destroy the affected plants so the trouble does not spread, and lay row covers to keep the egg-laying flies off the bed. Rotating your brassicas and skipping beds just worked with manure keeps the flies from finding your plants in the first place.
Fix:
- Remove and destroy affected plants
- Use row covers to exclude egg-laying flies
Stems shooting up as the leaves start to taste sharp
Warm days and shortening nights nudge mizuna to bolt, so it pushes up a flower stalk and the leaves lose their sweetness. This is nothing you did wrong, and once heat climbs toward 90°F (32°C) it is simply time to gather the crop while it still tastes lovely. Sow a fresh batch in late summer for a fall picking, and offer afternoon shade whenever a warm stretch rolls through.
Fix:
- Harvest promptly before flavor declines
- Resow in late summer for a fall crop
Little pinholes dotting your youngest leaves
Do not panic if you spot a scatter of tiny holes on young foliage, because this is almost always flea beetles, small dark insects that hop away the moment you lean in, and they trouble seedlings most. A floating row cover laid over the bed at sowing keeps them off from the start, and your plants grow up untouched. It also helps to set new plantings away from any brassica bed that struggled last year.
Fix:
- Cover plantings with floating row cover at sowing
- Relocate plantings away from previously infested brassica beds
Soft little insects gathering on the fresh growth
If green or gray specks are massing under the leaves and on the tender tips, and everything feels a bit sticky, you have found aphids, and they are easy to turn back. A firm spray of water washes most of them away, and a little insecticidal soap settles any that return. Going easy on nitrogen keeps the soft new growth they love from getting too lush, so they lose interest.
Fix:
- Rinse plants with a strong jet of water
- Apply insecticidal soap to affected foliage
Toxicity
Mizuna is a food crop and safe all around, grown for your table and gentle on cats, dogs, and every other animal about the place. There is no toxic part to keep away from anyone, so you can grow it without a second thought. The only mild note is the goitrogens shared across the cabbage family, and they matter only when livestock graze brassicas heavily for a long time.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
You can relax about cats. A curious taste of the peppery leaves does no harm, and only a very large mouthful of any greens might unsettle a stomach for a while.
Dogs None
There is nothing toxic here for dogs, so they are welcome near the plants. A little plain leaf now and then makes a perfectly fine treat.
Horses Safe
Horses can nibble mizuna quite safely. It sits in the mustard family, so let it stay a small extra rather than a main feed and all is well.
Rabbits Safe
Rabbits take happily to the tender leaves, which are a wholesome green for them. Just bring it in slowly, the gentle way you would offer any new fresh food.
Livestock Mild
Cattle, goats, and sheep can eat mizuna with no worry. Only long, heavy grazing on brassica forage risks the goitrogen effects the family shares, so mix it into other pasture and you are fine.
Birds Safe
Backyard hens and other birds may peck the leaves freely, nothing to fret over. The greens are a welcome bit of variety in their feed.
People Safe
Mizuna is a crop meant for your plate, lovely raw in a salad or softened into a warm dish. Healthy folks have nothing here to steer clear of.
Like other brassicas it contains glucosinolate goitrogens, which are mainly a concern for heavily grazed livestock rather than household pets.
Varieties
There are really only a couple of common kinds of mizuna, and the choice comes down mostly to color, so it is a relaxed decision. Both grow and taste much the same, so you truly cannot pick wrong.
Mizuna (green)
The everyday green kind you will meet most often has feathery, deeply notched leaves on slim white stems and a soft peppery taste that is easy to love.
Red Kingdom / purple mizuna
If you fancy a little color, the burgundy-tinged type with purple stems brings a pretty contrast to a bowl of mixed salad leaves.
How to propagate
Mizuna grows from seed and nothing else, and it is one of the kindest greens a beginner can start. Sow it right into the ground and you are only weeks away from your first cutting.
SeedEasy
Direct sow in early spring and again in late summer; succession sow for continuous harvest · Germinates in about 4-8 days at 55-75°F; baby leaves ready in roughly 21 days
Starting mizuna could hardly be simpler, since it grows straight from seed sown where it will stay. Tuck the seed just 1/4 to 1/2 inch deep into cool, moist soil and it comes up in about 4 to 8 days, with baby leaves to snip in roughly 21 days. Pop in a new short row every couple of weeks, grow it cut-and-come-again, and you will always have greens on hand.
Myths
Mizuna is a fierce, sharp mustard you must cook before eating.
You have nothing fierce to tame here, since the flavor stays mild with just a soft peppery lift. Raw in a salad is where it shines, and while it braises nicely too, cooking is only ever a choice you make for pleasure.
Mizuna is a warm-season green that needs summer heat to do well.
The truth is kinder to a beginner, because it is a cool-season crop that takes light frost in stride and is slow to run to flower. Spring and fall are when it thrives, while summer heat is the one thing that pushes it to bolt and turn bitter.