Leaf amaranth
Amaranthus tricolor
Also known asChinese spinach · Een choy / yin choi · Callaloo (Caribbean) · Bayam · Tampala · Joseph's coat
Environment
The bounded range this crop tolerates.
Climate and zones
- USDA zones
- 9–13 (winter low around -7°C)
- Frost
- frost sensitive (dies at first frost)
- Season
- warm (summer, frost-sensitive)
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 |
| Rockwool (Mineral wool) | alkaline until pre-soaked | very high | low |
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 | 0.8 |
| vegetative | 3 | 1 | 2 | 1.6 |
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
A strong hydroponic green for hot conditions where lettuce and spinach fail. Hold EC around 1.2-2.0 mS/cm and pH near 5.8-6.5. It does best around 25–32°C and takes heat that wrecks cool-season greens. Give moderate to high light, on the order of 18-28 mol/m2/day. Growth is quick: baby leaves in three to four weeks from seed, full leaves in six to eight. It suits NFT, deep water culture and vertical towers. Harvest cut-and-come-again, taking outer leaves while the centre keeps pushing new growth, and sow a fresh batch every two to three weeks for a steady supply. Feeding is moderate on a standard leafy-green mix. It bolts eventually but slower than lettuce in heat, and it stays fairly pest-free in soilless setups. Young leaves go raw into salad mixes; older ones cook down like spinach, which also cuts the oxalate. In aquaponics it does well on the warm, nutrient-rich water of tilapia systems, and the red and purple types add colour to a mix.