Mizuna, which is also known as Kyona, Shui Cai, Japanese mustard, Potherb mustard, California peppergrass, and Spider mustard, is a popular spicy green used fresh in salads or cooked in savory dishes. It’s both cold and heat tolerant and will withstand moderate summer weather without bolting. Serrated green leaves with white stems can quickly grow up to 18″ in length and, depending on the variety, are sweeter and milder when harvested young (6″ or shorter in length). The taste is milder than most mustards, with a slightly spicy and peppery flavor. Plants are adaptable to a variety of conditions and will produce a high yield of edible leaves.
Kyona mizuna leaves grow on very thin, white stalks that can become quite long, reaching up to 18″ if not harvested. Leaves are a medium to dark green and have a somewhat richer flavor than other mizuna varieties. The taste of these leaves can be even further improved by exposing plants to cool, early spring temperatures. This exposure “hardens” Kyona mizuna, making it become sweeter and more flavorful.
Seed Depth: 1/4″
Space Between Plants: 1″, thin to 6–12″ when seedlings have reached a height of 1″.
Space Between Rows: 18″
Germination Soil Temperature: 45–55°F
Days for Germination: 6–10
Sow Indoors: Start indoors approximately 4 to 5 weeks before average last frost date, if desired. However, we recommend sowing seeds outdoors to allow plants to harden.
Sow Outdoors: 4 to 6 weeks before average last frost or as soon as soil can be worked.
Although much more heat resistant that other leafy greens, mizuna prefers cooler weather and can still flower or bolt when temperatures become too hot. Seeds will germinate in temperatures as low as 45°F, so plant in the early spring in most climates and in the fall or early winter in warmer climates.
Natural: Full sun but will tolerate partial shade in hotter climates.
ARTIFICIAL: Plants will thrive under most types of artificial lights, but, as mizuna does not require high levels of heat, we recommend a basic fluorescent light set up. In the early stages of growth, ensure that your plants are getting between 10 and 12 hours of light a day. Keep lights at least 4–6″ away from the tops of your plants to prevent burning.
Soil: Will grow in most soil types but prefers well-drained loamy soils. A pH of 6.0 to 7.5 will keep plants nourished.
SOILLESS: Grows well in most soilless mixes but will do particularly well in mixes that contain coco coir.
Hydroponics: Like most other leafy greens, mizuna will thrive in hydroponic systems. Rock wool is a popular medium used by hydroponic growers of greens.
Aeroponics: Will thrive in an aeroponic system.
Water: Requires moderate but consistent watering. If soil dries out, plants may bolt and develop an even spicier flavor. Aim for 1″ per week.
Nutrients: As a leafy green, mizuna requires a significant amount of nitrogen. Apply a nitrogen-rich fertilizer approximately 4 weeks after planting.
Pruning: Keep an eye out for dead or wilting leaves and remove by pinching off or clipping.
Mulching: Straw may be applied around plants to keep moisture in the soil.
Rotation: Crops should be rotated to keep soil healthy. Avoid rotating with members of the cabbage family.
Companions: Grows well with bush beans, lettuce, cucumber, carrots, dill, spinach, onions, potatoes, and most herbs. Avoid planting with members of the cabbage family, bush beans, and strawberries.
Harvest: For baby greens, begin harvesting leaves when they reach 2″ in length. The younger the leaves, the more tender, so we recommend that you pick young leaves for salads and save mature leaves for cooking. Leaves can be picked by hand starting on the outside and allowing the smaller ones to mature. Although allowing the plant to mature before picking will keep it healthy, don’t allow leaves to grow to full size before harvesting since they have a tendency to become pretty tough. The entire plant can also be harvested by cutting the stalk 1″ above soil level.
Storage: As a leafy green, mizuna will not keep well for much longer than a week or so. Keep stored in the refrigerator in a bag with moist paper towels.
Seed Saving: Saving seeds from the mizuna plant is extremely easy and will help set you up for growing mizuna in subsequent seasons. To harvest seed, allow some of your plants to flower and develop seed pods. Once your pods have turned brown and are brittle to the touch, cut down the stalks and transfer to a warm area with little humidity to allow the pods to further dry out. Place pods in a bag or pillowcase (sans holes!) and crush the pods to separate from the seeds. Filter seeds through a mesh strainer or winnow to remove the chaff.
Preserve: This plant is excellent for pickling or fermenting, kimchi style.
Prepare: Pickling mizuna is extremely easy and can be done in 24 hours. To pickle, place a layer of mizuna and cover with salt. Continue adding more layers of mizuna and salt until you have run out of greens. Place a weight on the top layer and leave overnight in the refrigerator. Squeeze out the excess water before eating. If eating raw, simply rinse and chop!
Nutritional: Contains significant levels of antioxidants as well as vitamin(s) C, K, and A.
Medicinal: Similar to other cruciferous vegetables, some studies have shown that mizuna may possess nutrients that can help prevent certain types of cancer, such as breast, colon, prostate, and lung. It has also been cited as being beneficial for the cardiovascular system as it can help lower cholesterol.
For a healthy, Asian-inspired dinner, try this Mizuna-Based Stir-Fry.