Cardoon
Cynara cardunculus
Also known asCardo · Artichoke thistle · Cardon
Environment
The bounded range this crop tolerates.
Climate and zones
- USDA zones
- 7–10 (winter low around -18°C)
- Frost
- frost hardy
- Season
- cool (spring/fall)
Growing systems
Root mass: heavy. Thin-channel systems can't hold this crop.
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 | 2 | 1 | 1 | 1 |
| vegetative | 2 | 1 | 2 | 1.6 |
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 specialty crop for large systems where space is not tight. Each plant wants one to two square metres and a big root zone, a 40 L container or deep media bed. Hold EC around 1.4-2.0 mS/cm and pH 6.0-7.5. It is a Mediterranean crop, best at 12–24°C, preferring cool conditions but taking mild frost. Give full sun, 18-28 mol/m2/day. The key step is blanching: three to four weeks before harvest, wrap the leaf stalks in cardboard, paper or opaque fabric to exclude light, which reduces bitterness and pales the stalks from green to white-yellow; unblanched stalks are unpleasantly bitter. From transplant the crop is long, 120 to 150 days, harvested by cutting the blanched stalks at the base. In mild climates it is perennial and regrows each spring; in colder areas grow it as an annual or mulch the crown over winter. Some varieties are spiny, so wear gloves at harvest.