Black radish, the winter radish

Black radish

Black radish or winter radish is a strikingly delicious root vegetable with a light spicy taste.

Black radish key facts

Name – Raphanus sativus niger
Family – Brassicaceae
Type – annual

Height – 8 to 12 inches (20 to 30 cm) depending on the variety
Exposure – full sun
Soil – rather rich and well drained

Sowing – May to October
Harvest – from September to December

Black radish is harvested before the first frost spells. From sowing to harvest, here are the best practices to grow it.

Sowing black radish

Sowing black radish is easy and can be performed all summer long directly in the ground.

Simply cover with a little ground and/or soil mix, and water often to quickly harvest beautiful fresh radishes…

Sowing black radish, winter radish

They are sown from May to September/October depending on the climate.

  • Sow the seeds directly where they are to grow.
  • Trace furrows ½ to 1 inch (2-3 cm) deep.
  • Sow the seeds by spacing them regularly, about one seed every 1¼ to 1½ inches (3 to 4 cm).
  • Cover the furrows over without pressing the soil down too much.
  • Water regularly with a fine drizzle.

Once the seeds have sprouted, thin them out. This means removing the weakest sprouts and only keeping the most vigorous ones, spaced every 6 to 8 inches (15 to 20 cm).

  • Ensure the ground stays clear of weeds by removing them as they appear.
  • Lightly break the surface regularly with a small hoe to let water trickle down to the roots.

You also have the option to sow your black radish in a garden box, with soil mix and regular watering. This will give you nice radishes to nibble straight from your terrace or balcony!

Growing and caring for black radish

Once they have been sown, the only care they need is regular watering, especially in case of high temperatures in summer.

  • Water frequently in summer to ensure that the soil remains cool.
  • Apply mulch on the ground to sustain soil coolness.

Harvesting black radish, winter radish

Black radish harvest is preferably targeted before the first frost spells but they can also be harvested during the entire winter.

Black radish harvest generally takes place at least 4 months after sowing.

  • Harvesting before the ground freezes over makes pulling them out less work.
  • A good hint for timing the harvest: the tip of the black radish will start jutting out of the ground.
  • Once harvested, dry the black radish outdoors, but keep them out of the rain.
  • After that, keep the black radish in a dry, cool and well ventilated spot. The ‘Noir long maraicher’ keeps for a very long time in winter.

Properties of black radish

With high levels of vitamins B and C, phosphorus and magnesium, it also has diuretic properties.

Black radish on a set of planksIt is excellent to purge the liver and gall bladder, by imparting tonic benefits for digestion.

  • Black radish is a very low-calorie food.
  • Black radish has high fiber content.
  • It enhances gall bladder juices, which helps clean and detoxify the liver.
  • It is frequently used against kidney stone and gall stone.

Ingesting black radish in the evening ensures proper nutrient absorption, and also fends off insomnia.

You can ingest black radish raw or cooked, or even in the form of black radish juice. But it is also possible to purchase black radish capsules in a pharmacy, ready to swallow.

Species and varieties of black radish

Even though it spread across Europe in the XVIth century, black radish only recently reappeared on the market.

Sometimes, black radish is mistaken to be horseradish. To confuse things even further, black radish is sometimes called “cultivated horseradish” or “Paris horseradish”.

There are a great many options for growing black radish varieties!

  • ‘Noir gros rond d’hiver’, also called ‘Black Spanish round’: rapid growth, excellent conservation, tolerance to short frost spells.
  • ‘Noir gros long d’hiver’, also called ‘Black Spanish long’: rather longer than wide, it can reach 12 inches (30 cm) in length and also keeps very well.
  • ‘Noir long poids d’horloge’, also called ‘Noir long maraicher’: very black skin, cylindrical, 8 to 10 inches (20 to 25 cm) long.
  • ‘Serpent’ or ‘Rattail’ – this one is harvested before maturity, the initial swelling of the root is harvested. As thick as a pencil, often violet-colored. Nibble when fresh or pickle with vinegar.
  • ‘Violet de Gournay’ or ‘Gournay’: One of the radishes with the mildest flesh, its skin is a pinkish purple and it keeps very well.

In the group of black radish native to Asia, you’ll find:

  • ‘Okhura’ – very mild radish, it produces round white roots.
  • ‘China rose’ – can be sown in fall and in spring. Long pink roots.
  • ‘Ilka’ – mild, juicy flesh, round, dark pink, roots about 4 to 6 inches (10 to 15 cm) across.

Smart tip about radishes

To have crunchy black radishes all season long, it’s a good idea to sow small batches every once and a while. Sowing every 2 to 3 weeks guarantees always having ready-to-eat radishes at hand.


Images: adobestock: jolentil, CC BY 2.0: Christian Haselbach