Crosnes
Stachys affinis
Also known asChinese artichoke · Japanese artichoke · Knotroot · Artichaut de Crosnes · Chorogi
Environment
The bounded range this crop tolerates.
Climate and zones
- USDA zones
- 5–9 (winter low around -29°C)
- Frost
- very hardy (survives deep cold)
- Season
- cool (spring/fall)
Growing systems
Root mass: moderate.
Growing media
| Medium | pH effect | Retention | Bacterial surface |
|---|---|---|---|
| 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 | 2 | 1 | 2 | 1.3 |
Aquaponics suitability
Not recommended
Fish waste alone doesn't supply enough of what this crop demands. Grows in hybrid systems with supplemental dosing, but expect active management.
Care notes
A niche crop requiring soil or deep media bed growing (the tubers form underground along spreading stolons). Not suited to NFT, DWC, or other water-culture systems. Media beds with 15 cm of loose substrate (perlite, expanded clay, or coir) can produce crosnes. EC 1.0-2.0 mS/cm. pH 6.0-7.0. Temperature: 12–22°C (cool-season crop; tuber formation is triggered by shortening day length in autumn, similar to potatoes). Moderate light (DLI 12-18 mol/m2/day). Plant tubers or divisions in spring, 5–8 cm deep. The above-ground foliage looks like a typical mint-family plant (square stems, opposite leaves, 30–40 cm tall). Harvest tubers in late autumn after the foliage dies back. Dig carefully to retrieve the small, fragile tubers. Yields are modest: perhaps 200–500 g per plant. The tubers deteriorate quickly after harvest (they dry out and lose crispness within days); eat or pickle them promptly. Despite the difficulty, crosnes are a fascinating specialty crop with a devoted following among chefs and adventurous eaters. The distinctive spiral shape makes them a conversation piece on the plate.