Black Salsify

About

Scorzonera has a black skin, white flesh and a delicate flavour that Victorian cooks compared to oysters. The comparison is generous and the vegetable is good, sweet and slightly nutty, and nothing else in the garden tastes like it.

It is also a perennial pretending to be an annual, which gives it a useful property no other root crop has. A row that produces thin roots in its first autumn can be left in the ground and lifted a year later, by which time the roots have thickened considerably. Nothing is wasted by a poor first season.

The difficulty is entirely in the lifting. The root is long, brittle and inclined to snap at the slightest leverage, and a snapped root bleeds latex and does not keep.

Appearance and character

A long, straight, cylindrical taproot, 20 to 30 cm long and 2 to 4 cm across, with a matt black or very dark brown skin.

Flesh is pure white, firm and slightly fibrous towards the outside, exuding a white milky latex when cut.

Leaves are narrow, strap-shaped and grass-like, smooth-edged, in a fresh mid-green, forming an upright rosette that is easily mistaken for a clump of coarse grass.

In its second year the plant sends up a branched flowering stem to a metre with large yellow dandelion-like flowers that smell faintly of vanilla in the morning, followed by clocks of parachute seeds.

The flower buds picked before opening are a vegetable in their own right, steamed and dressed.

Where it is from

Scorzonera is native to southern Europe and western Asia, growing on dry grassland and limestone.

Cultivation as a vegetable began in Spain and Italy in the sixteenth century. The name comes either from the Catalan escorso for viper, through the belief that the root treated snakebite, or from the Italian scorza nera, black bark. Both derivations are defended and neither is settled.

It reached northern Europe in the seventeenth century and became a standard kitchen-garden crop in France, Belgium and the Netherlands, which grow most of the commercial crop today.

Britain grew it widely in Victorian kitchen gardens and then largely forgot it, which is why it now reads as an unusual vegetable in a country that once treated it as ordinary.

How it grows

Sow direct where the plants are to grow. The taproot forks if disturbed.

Use fresh seed. Like parsnip, scorzonera seed loses viability quickly, and year-old seed germinates poorly.

Sow from March to April at 1 cm deep in rows 30 cm apart, and thin to 10 to 15 cm apart. Germination takes two to three weeks.

Roots are ready from October, around six months from sowing.

Lift by digging a trench alongside the row with a fork and easing the roots out sideways. Pulling straight up snaps them.

Leave thin roots in the ground over winter and through a second summer, cutting off any flower stems that appear. They thicken substantially and lift the following autumn.

Through the seasons

Early spring is the sowing window, from March into April, into a deep stone-free bed prepared the previous autumn and not manured since.

Late spring thins the seedlings to 10 to 15 cm and keeps the row weeded. The grass-like leaves are easy to hoe off by mistake.

Summer is watering and weeding. Remove any flower stems from first-year plants, which divert energy from the root.

Autumn and winter are the harvest. Lift from October, digging a trench alongside. Roots are fully hardy and are best left in the ground and lifted as needed through to March.

The second year is optional and worthwhile. Leave undersized roots in place, cut off flower stems, and lift the following autumn.

Care difficulty

Moderate, and the crop asks little through the season.

Lifting is the real skill and the reason people give up on it. Dig a trench alongside the row to the full depth of the root and lever it sideways into the trench. A garden fork used as a lever from above snaps the root every time.

Germination is slow and the seed is short-lived, so buy fresh each year.

Stone-free ground is needed as for any long root crop, and fresh manure forks the roots.

Weeding needs care while the seedlings are small, because narrow grass-like leaves are hard to tell from grass.

Bolting in the first year happens after a hot dry spell and is uncommon. Cut the flower stem off and the root continues.

Watering

Water weekly in dry spells. Around 12 litres per square metre, given as a soak that reaches root depth.

Even moisture gives smooth straight roots, and interrupted moisture gives split or forked ones.

Keep the seedbed damp through the two to three weeks of germination.

Mulch between the rows once the plants are thinned, which holds moisture and keeps down the weeds that swamp the narrow seedlings.

Second-year plants need less water than first-year ones, having a root system already in place.

Container growing needs a pot at least 40 cm deep and gives shorter roots than open ground.

Warning signs, diseases and pests

Roots snapping on lifting is the commonest problem and is a technique fault. Trench alongside and lever sideways.

Slugs graze the crown and the shoulders of the root where they sit proud of the soil. Earth up lightly and patrol on damp evenings.

White blister shows as raised chalky pustules on the leaves and distorted growth. Remove affected leaves and space the plants for airflow. It rarely affects the crop.

Forked or stubby roots mean stones, compaction or fresh manure.

Splitting follows irregular watering.

Bolting in the first year, after heat or drought, sends up a flower stem. Remove it and the root carries on.

The white latex from cut roots stains hands and clothes. Wear gloves and it washes off with soap.

Growing environment

Full sun to light shade. An open position gives the straightest roots.

Deep, light, stone-free soil is the requirement. Dig to a spade and a half, remove stones, and break up any pan. This is the crop that most rewards proper bed preparation.

Lime to pH 6.5 or 7.

Never sow into freshly manured ground. Follow a crop that was manured the previous season, and add well-rotted compost the autumn before if the bed needs organic matter.

Rake to a fine tilth before sowing.

Raised beds of sieved soil grow good roots where the natural ground is stony.

Rotate on three or four years, though scorzonera shares few diseases with anything else in the garden.

Feeding

Scorzonera needs very little. On soil in reasonable heart it needs nothing at all.

Avoid nitrogen, which gives a mass of leaf over a thin forked root.

A dressing of sulphate of potash at 15 g per square metre before sowing helps on poor or sandy ground.

Never apply fresh manure.

Second-year plants benefit from a light potash dressing in spring.

Troubleshooting

The roots snapped as I lifted them. Dig a trench alongside the row to the full depth of the root and lever the roots sideways into it.

Forked or stubby roots. Stones, compaction or fresh manure. Dig a deep stone-free bed and follow a crop manured last year.

Thin roots at the end of the first season. Common, and easily fixed. Leave them in the ground, cut off any flower stems, and lift the following autumn.

Nothing germinated. Old seed. Buy fresh each year, since viability drops after a season.

A flower stem in the first summer. Bolting after heat or drought. Cut it off and the root continues to fill.

Sticky white sap all over my hands. Latex from the cut root. Harmless, and it washes off with soap. Wear gloves.

Chalky white pustules on the leaves. White blister. Remove affected leaves and improve airflow. It seldom reduces the crop.

Do I peel it? Peel it after cooking rather than before, which is much easier and loses less flesh. Drop peeled roots into water with lemon juice, since the flesh browns quickly.