Edible plant · roots bulbs

Scorzonera

Scorzonera hispanica

Also known asBlack salsify · Spanish salsify · Black oyster plant · Serpent root · Viper's grass

intermediate cool-season single
Days to harvest
120–180
Yield / plant
0.2kg
Spacing
10 cm
Daily light
14–20DLI

Environment

The bounded range this crop tolerates.

Temperature
5°C15°C25°C35°C
724°C
pH
45.578.5
6–7.5
EC (hydro)
01234
1–1.6 mS/cm
Daily light
515253545
14–20 mol/m²/d
Single harvest

Climate and zones

USDA zones
3–9 (winter low around -40°C)
Frost
very hardy (survives deep cold)
Season
cool (spring/fall)
Outdoor year-round (in zone)
Outdoor in growing season
Unheated greenhouse / hoop
Heated greenhouse
Indoor (heated home)
Indoor hydroponics + grow lights

Growing systems

Root mass: heavy. Thin-channel systems can't hold this crop.

Deep water culture (rafts)
NFT channels
Vertical / aeroponic tower
Drip / Dutch buckets
Media bed (ebb and flow)
Wicking bed
Soil bed

Growing media

MediumpH effectRetentionBacterial 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.

StageNPKEC (mS/cm)
seedling1110.6
vegetative1121.3

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 deep-rooted crop requiring 30 cm of loose, stone-free growing medium. Media beds or tall containers. EC 1.5-2.5 mS/cm. pH 6.0-7.0. Temperature: 1022°C (cool-season). Moderate light (DLI 12-18 mol/m2/day). From seed to harvest: 110-130 days (long season). Direct seed; the taproot doesn't survive transplanting. Thin to 810 cm spacing. Harvest by loosening the media deeply and pulling carefully; the roots snap easily and the latex makes them slippery. Process immediately: peel with a vegetable peeler (the black skin comes off easily), drop into acidulated water. For roasted scorzonera: toss peeled pieces with olive oil, roast at 200°C until golden and caramelized. The flavor is sweet, earthy, and refined. The root stores for several weeks in damp sand at 14°C. For aquaponics growers interested in unusual European root vegetables, scorzonera rewards patience with a unique, delicate flavor.

Further reading