Daikon

Daikon is the large-rooted winter radish, growing long white cylindrical roots that reach 25–40 cm and stay crisp and mildly pungent rather than sharp. It is a cool-season root crop that sizes up as days shorten and tolerates frost in the ground, so it holds far longer than a summer radish. Black and round winter radishes belong to the same group and are grown the same way. It needs a deep, loose, stone-free bed to form a straight unforked root.

Growing

Sow directly where the crop will grow — the taproot resents transplanting and will fork if disturbed. Loosen the bed to at least 30 cm and remove stones before sowing; compacted or stony soil is the usual cause of split and forked roots. Place seeds 1 cm deep and thin to 15 cm apart once seedlings have two true leaves. Sow once soil temperature reaches 5 °C, but time the main crop so the roots size up in cool, shortening days — heat and long days push the plant to bolt instead of to root. Sow in succession every two to three weeks for a continuous supply.

Care

Keep soil evenly moist but not waterlogged — irregular watering causes cracked, hollow or pithy roots. Feed lightly with a balanced fertiliser at sowing; excess nitrogen builds leaf at the expense of root. Weed around young plants, which are slow to compete until the leaf canopy closes. Watch for flea beetle on young seedlings; a fine mesh cover over the row is the simplest protection.

Harvest

Harvest when roots are 25–40 cm long and 4–7 cm across, lifting with a fork rather than pulling by the leaves. Pull one test root to judge the crop; over-mature roots turn hollow, woody and hot. Roots stand in the ground through light frost and can be lifted as needed, which improves both flavour and texture. Lift the crop before the ground freezes hard, or before the plant runs to seed in warm weather.

In the kitchen

Grated raw, daikon is the classic crisp condiment alongside grilled fish and fried food, and it shreds into salads and slaws. Simmered in stock it turns translucent and sweet, absorbing whatever it is cooked in — the basis of oden and of many braises. Cut into batons or half-moons it takes a quick pickle in salt, sugar and rice vinegar in a matter of hours. Black and round winter radishes are sharper and are better sliced thin with salt and oil, or grated into a remoulade. The young leaves are edible and add a mustard bite to soups and stir-fries.

Storing

Remove the tops before storing, or they will draw moisture out of the root. Whole roots keep unwashed in a perforated bag in the refrigerator for 2–3 weeks. In a cool, humid cellar at 0–4 °C, packed in damp sand, they keep for 2–4 months — this is the classic winter store. Pickled in brine or rice vinegar they keep for several months in the refrigerator. Do not freeze raw; the texture collapses on thawing.