Mizuna
Brassica rapa var. japonica
Traditional brassica green of Japanese origin prized for its quick growth, productivity, mild flavor, and recognizable, serrated leaf shape. USDA Certified Organic.
Harvest
21-45d
Days to harvest
Sun
Full sun to partial shade
Zones
5–11
USDA hardiness
Height
3 feet
Planting Timeline
Showing dates for Mizuna in USDA Zone 7
All Zone 7 brassica →Zone Map
Click a state to update dates
Mizuna · Zones 5–11
Growing Details
Zone-by-Zone Planting Calendar
| Zone | Indoor Start | Transplant | Direct Sow | Harvest |
|---|---|---|---|---|
| Zone 3 | March – April | May – June | May – June | June – October |
| Zone 4 | March – April | May – June | April – June | May – October |
| Zone 5 | February – March | April – May | April – May | May – November |
| Zone 6 | February – March | April – May | April – May | May – November |
| Zone 7 | February – March | April – May | March – May | April – November |
| Zone 8 | January – February | March – April | March – April | April – December |
| Zone 9 | January – January | February – March | February – March | March – December |
| Zone 10 | January – January | February – March | January – March | February – December |
Complete Growing Guide
Start mizuna from seed directly in your garden beds, as it doesn't transplant well due to its taproot. Prepare your soil by working in 2-3 inches of compost or well-aged manure to create the loose, fertile growing medium mizuna thrives in. The ideal soil pH ranges from 6.0-7.0, and good drainage is essential to prevent root rot.
Sow seeds ¼ inch deep in rows spaced 12 inches apart, then thin seedlings to 4-6 inches between plants for full-sized heads or 2-3 inches for baby leaf harvests. In zones 3-6, plant mizuna in early spring (2-4 weeks before last frost) and again in late summer for fall harvest. Southern gardeners in zones 7-10 can grow mizuna through winter, making it an excellent cool-season green when other crops struggle.
Succession plant every 2-3 weeks to ensure continuous harvests throughout the growing season. Mizuna performs best in temperatures between 50-70°F and will bolt quickly once temperatures consistently exceed 75°F. In hot climates, provide afternoon shade or use shade cloth during summer months.
Fertilize lightly at planting with a balanced organic fertilizer, then side-dress with nitrogen-rich compost or fish emulsion every 3-4 weeks. Avoid over-fertilizing with nitrogen, which can make leaves tough and overly peppery. Maintain consistent soil moisture with 1 inch of water weekly, using mulch to retain moisture and suppress weeds.
Common mistakes include planting too thickly (leading to weak, spindly plants), harvesting too late (leaves become bitter), and growing in hot weather without protection. Maximize yields by harvesting outer leaves regularly to encourage continued production, and plant in blocks rather than single rows to create beneficial microclimates that help plants stay cool and retain moisture.
Harvesting
Begin harvesting mizuna baby leaves when they reach 3-4 inches tall, typically 21-30 days from seeding. For full-sized leaves, wait until they're 6-8 inches long with fully developed feathery serrations, usually around 40-45 days. The best visual cue is when leaves have a bright green color and crisp texture—avoid yellowing or wilted leaves which indicate the plant is stressed or bolting.
Harvest in early morning when leaves are fully hydrated and crisp. Use clean scissors or a sharp knife to cut outer leaves first, leaving the growing center intact for continued production. Cut leaves about ½ inch above soil level to avoid damaging the crown. You can harvest individual leaves or cut the entire plant 1 inch above ground—mizuna will regrow 2-3 times before declining in quality. Stop harvesting once flower buds appear, as leaves become increasingly bitter and tough.
Storage & Preservation
Fresh mizuna keeps best when stored immediately after harvest. Rinse leaves in cold water, spin dry thoroughly, and store in perforated plastic bags in the refrigerator crisper drawer. Properly stored mizuna maintains quality for 7-10 days at 32-35°F with high humidity.
For preservation, mizuna freezes well when blanched for 30 seconds in boiling water, then shocked in ice water and drained. Frozen mizuna works excellently in cooked dishes but loses its crisp texture for raw applications. Dehydrate young leaves at 95°F for crispy snacks or grind dried leaves into seasoning powder. Mizuna also ferments beautifully—try adding it to kimchi or sauerkraut for a mild peppery note that complements stronger flavors without overwhelming the ferment.
History & Origin
Mizuna (Brassica rapa var. nipposinica) originated in the Kansai region of Japan, particularly around Kyoto, where it has been cultivated since at least the 16th century. The name 'mizuna' translates to 'water greens,' reflecting its traditional cultivation method in flooded fields during winter months. Japanese farmers developed this variety specifically for cool-season production, selecting for its exceptional cold tolerance and ability to grow in wet conditions.
Historically, mizuna served as a crucial winter vegetable when few other greens could survive Japan's harsh winters. It became deeply integrated into Kyoto's culinary culture, appearing in traditional hot pot dishes and as pickled vegetables. The variety remained relatively unknown outside Japan until the 1980s when specialty seed companies began introducing Asian vegetables to Western markets. Today's mizuna varieties still closely resemble their historical ancestors, making this a true heirloom with an unbroken chain of cultivation spanning over 400 years.
Advantages
- +Exceptional bolt resistance in cool weather extends harvest window significantly
- +Cut-and-come-again growth provides 3-4 harvests from single planting
- +Rapid 21-day baby leaf harvest perfect for impatient gardeners
- +Thrives in partial shade where other greens struggle
- +Naturally pest-resistant due to quick growth cycle
- +Beautiful feathery foliage doubles as ornamental garden accent
- +Mild peppery flavor appeals to those who find arugula too strong
Considerations
- -Bolts rapidly in temperatures above 75°F, limiting summer growing
- -Flea beetles can quickly riddle young leaves with holes
- -Short shelf life requires frequent harvesting and immediate use
- -Poor transplant success due to sensitive taproot system
- -Becomes bitter and tough once flowering begins
Companion Plants
Plant Together
Lettuce
Shallow roots don't compete, provides living mulch and maximizes space usage
Radishes
Helps break up soil, deters flea beetles that commonly attack brassicas
Carrots
Deep taproot doesn't compete with shallow mizuna roots, improves soil structure
Onions
Strong scent repels cabbage worms, aphids, and other brassica pests
Dill
Attracts beneficial insects like parasitic wasps that control cabbage pests
Nasturtiums
Acts as trap crop for flea beetles and aphids, draws pests away from mizuna
Spinach
Similar growing requirements, harvested at different times for succession planting
Chives
Repels aphids and cabbage worms with sulfur compounds
Keep Apart
Strawberries
Can inhibit growth of brassicas and may compete for similar nutrients
Tomatoes
May stunt brassica growth and attract pests that also damage mizuna
Pole beans
Can shade mizuna excessively and compete for nitrogen in soil
Nutrition Facts
Per 100g serving. % Daily Value based on 2,000 calorie diet. Source: USDA FoodData Central (FDC #747447)
Pests & Disease Resistance
Resistance
Good bolt resistance in cool weather. Generally pest and disease resistant due to quick growth.
Common Pests
Flea beetles, aphids, cabbage worms (less susceptible than other brassicas)
Diseases
Rarely affected due to quick growing cycle. Occasional downy mildew in humid conditions.