Parsley
Petroselinum crispum
Also known asFlat-leaf parsley · Italian parsley · Curly parsley · Persil
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: moderate.
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 | 2 | 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
A staple hydroponic herb with steady demand. EC 1.0-1.6 mS/cm. pH 5.5-6.5. Temperature: 10–24°C (cool to moderate; tolerates heat better than cilantro but bolts in sustained temperatures above 28°C). Moderate light (DLI 12-18 mol/m2/day). NFT, DWC, Kratky or media-bed systems all work. Seed germination is slow (2-3 weeks) and erratic; soaking seed overnight in warm water speeds it up. From seed to first harvest: 8-10 weeks, making it one of the slower herbs from seed. Harvest outer stems at the base while the plant keeps producing from the centre for months. Flat-leaf varieties ('Giant of Italy', 'Titan') are preferred for commercial production for their stronger flavour and faster regrowth after cutting. Parsley is biennial: in its second year it flowers, sets seed and dies, so for continuous supply succession plant annually. It is relatively pest-free, and Italian flat-leaf parsley is a core commercial crop alongside basil, cilantro and mint.