Nasturtium
Tropaeolum majus
Also known asIndian cress · Tropaeolum · Garden nasturtium · Capucine · Mastuerzo
Environment
The bounded range this crop tolerates.
Climate and zones
- USDA zones
- 9–11 (winter low around -7°C)
- Frost
- frost sensitive (dies at first frost)
- Season
- warm (summer, frost-sensitive)
Growing systems
Root mass: light.
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 | 0.5 |
| 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 easy, fast-growing plant for hydroponic systems, valued primarily for its edible flowers and peppery leaves. EC 1.0-1.5 mS/cm (deliberately low; rich conditions produce excessive leaf growth at the expense of flowers). pH 6.0-7.0. Temperature: 15–25°C (cool to moderate; heat above 30°C reduces flowering). Moderate light (DLI 14-20 mol/m2/day). DWC, media beds, or large containers. From seed to first flowers: 6-8 weeks. The flowers appear continuously for months once they start. Harvest flowers in the morning when they're freshly opened. The leaves are harvestable throughout growth. Under-feeding (low nitrogen) promotes flowering; overfed nasturtium produces lots of leaves and few flowers. For the pickled seed pod 'capers': harvest green, immature seed pods (before they harden) and pickle in salted white wine vinegar with peppercorns and bay. Bush varieties are better for contained hydroponic systems; trailing types work well in hanging baskets or cascading over the edge of media beds.