Celtuce
Lactuca sativa var. asparagina
Also known asStem lettuce · Asparagus lettuce · Chinese lettuce · Celery lettuce · Wosun · Woju · A-choy (leaves)
Environment
The bounded range this crop tolerates.
Climate and zones
- USDA zones
- 4–9 (winter low around -34°C)
- Frost
- tolerates light frost
- Season
- cool (spring/fall)
Growing systems
Root mass: moderate.
Growing media
| Medium | pH effect | Retention | Bacterial surface |
|---|---|---|---|
| Expanded clay pebbles (LECA) | neutral / inert | low | high |
| Coco coir (Coconut coir) | slightly acidic | high | moderate |
| 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
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
An interesting and underappreciated hydroponic crop. Culture is the same as lettuce. EC 1.0-1.8 mS/cm. pH 5.5-6.5. Temperature: 15–22°C (cool-season, like all lettuce). Moderate light (DLI 12-17 mol/m2/day). NFT, DWC, or media bed systems all work. From seed to stem harvest: 60-80 days (longer than leaf lettuce because you're waiting for the stem to thicken). Harvest the stem when it reaches 3–5 cm diameter and before flower buds appear at the top. Peel the tough outer skin of the stem to reveal the crisp, pale green interior. Slice the peeled stem into thin rounds or matchsticks for stir-frying, pickling, or eating raw in salads. The texture is similar to broccoli stems or water chestnuts: crispy and juicy. The leaves can be harvested progressively as the stem grows, treating the plant as a dual-purpose crop. Celtuce is rarely seen at farmers' markets or grocery stores outside Chinese neighborhoods, which represents an opportunity for hydroponic growers serving diverse communities. The novelty factor alone generates interest and conversation at market stalls.
Notable varieties
| Cultivar | Type | Days | Notes |
|---|---|---|---|
| Summer 38 | open pollinated | 80 | Modern slow-bolt selection. Holds in heat up to about 30C without toughening, useful where summer arrives early. Stems 30+ cm by harvest. The variety most US Asian-vegetable seed catalogs carry. |
| Red Mountain | open pollinated | 70 | Heirloom selection with deep purple-bronze foliage on green stems. Less productive than Summer 38 but the visual draw is the appeal. Same culinary use, leaves work in salad mixes for color. |
| Qingsun No. 1 | open pollinated | 75 | Chinese commercial cultivar (青笋一号), uniform thick stems, the type sold at Chinese-American markets. Harder to find from Western seed catalogs but standard in Asian seed houses. |