Mizuna
Brassica rapa var. nipposinica
Also known asJapanese mustard greens · Kyona · Spider mustard
Environment
The bounded range this crop tolerates.
Climate and zones
- USDA zones
- 4–9 (winter low around -34°C)
- Frost
- frost hardy
- Season
- cool (spring/fall)
Growing systems
Root mass: light.
Growing media
| Medium | pH effect | Retention | Bacterial surface |
|---|---|---|---|
| Rockwool (Mineral wool) | alkaline until pre-soaked | very high | low |
| Expanded clay pebbles (LECA) | neutral / inert | low | high |
| Coco coir (Coconut coir) | slightly acidic | high | moderate |
| Net pot, no medium (Bare-root) | - | - | - |
| Soil-based mix (Potting soil) | varies | high | high |
Nutrient demand by stage
NPK ratios are relative weights. EC targets shift through the plant's life.
| Stage | N | P | K | EC (mS/cm) |
|---|---|---|---|---|
| seedling | 1 | 1 | 1 | 0.6 |
| vegetative | 3 | 1 | 2 | 1.4 |
Aquaponics suitability
Compatible
Fish waste provides enough nitrogen for healthy growth. Supplemental potassium, calcium, and iron may still be needed depending on fish stocking density.
Care notes
One of the easiest and most productive hydroponic Asian greens. EC 1.0-2.0 mS/cm. pH 5.5-7.0. Temperature: 10–25°C (cool-season; more heat-tolerant than lettuce before bolting). Moderate light (DLI 12-18 mol/m2/day). Any hydroponic system works. From seed to baby leaf: 3-4 weeks. Full-sized rosettes: 5-7 weeks. Harvest outer leaves for cut-and-come-again production over 6-8 weeks. The frilly leaf texture makes mizuna a salad mix essential; it adds volume, visual appeal, and a mild peppery accent without overwhelming other flavors. Succession plant every 2-3 weeks. Red/purple varieties ('Red Knight', 'Ruby Streaks') add dramatic color contrast in salad blends. Pest issues are minimal compared to other brassicas. For commercial hydroponic salad mix producers, mizuna is a core component: fast-growing, attractive, and with consistent demand from restaurants and retailers. A top-tier hydroponic crop for any grower.