679 Raphanus sativusCommon Names: radish, redish, bier radish, daikon Family: Brassicaceae (cabbage Family)
The radish is an extremely variable species of garden vegetable. Cornucopia II: a Source Book of Edible Plants lists a sampling of 82 different cultivars available in the US. Some radishes are annuals, little more than 4 in (10 cm) tall at maturity, and some are biennials, going to seed in their second growing season, and topping out at over 6 ft (1.8 m) in height. Most radish types are grown for their enlarged roots, and there is great variation in size, shape and color. Some are small "salad radishes" with red skins or pure white throughout. These are mostly cool-season annuals, harvested young and usually eaten raw. Other radishes get huge, up to 60 lb (27 kg). Most of these "daikon" types are biennials, harvested after a longer growing season, and cooked before eating. Some radish roots have black or green skins. Some have pink flesh. Some radish cultivars are grown just for the seed pods which are delicious raw, pickled or in stir fry. These are called bier radishes in Germany (and served raw with beer), and rat-tailed radishes in the Far East (although not, as far as we are aware, served with rats). Some radish cultivars are grown for the high quality oil that is extracted from the seeds. There are even cultivars grown for the leaves which are cooked as potherbs, and some grown for sprouting.
Radish leaves usually are medium green and lobed and have a rough texture, but some are purplish and some are smooth. The flowering stalks stand 2-5' above the leaves, depending on the variety. The flowers are cross-shaped with four petals, usually about an inch across and white, pink or purple. The seed pods are sickle shaped, 2-12 in long, first green, then turning brown when mature. They are full of little round seeds.
The original plant from which cultivated radishes were derived is believed to be the charlock (Raphanus raphanistrum), a common weed of seasides and sandy soils in Europe and the UK. The Egyptians were cultivating radishes 3000 years before Christ. The radish reached China by 500 BC. Today the radish is the most widely grown vegetable in Japan.
CultureSalad radishes are best when grown fast and picked when young and crisp. They become fibrous and overly pungent in hot weather or if left in the ground too long. Make a succession of plantings so that there will be some radishes at peak quality throughout the season. Plant a short row every week. Light: Radishes will grow best in full sun, but they will still grow in semi-shade. Moisture: Regular garden moisture. Hardiness: USDA Zones 3 - 10. The salad radish is an annual that does best in cool weather. In northern areas plant salad radishes before the last expected frost in spring; in the south, plant in autumn or winter. They are not hurt by frost. Cold weather makes them sweeter. Bier (a.k.a. rat-tail) radish will not produce pods when temperatures fall below about 45F, so plant these in spring for late spring and early summer harvest. The larger daikon-type radishes can be planted in spring for summer harvest, or planted in fall and overwintered for harvest the following spring, before the shorter nights of summer induce them to go to seed. Propagation: Radish seeds germinate in 3-7 days.
In Europe and North America, red skinned and white radishes are grown mainly as salad plants and eaten raw. In Asia, larger daikon type radishes are important sources of food. They are cooked in various ways and preserved by pickling or drying. From one variety or another, the leaves, stems, flowering shoots, seed pods, seeds, sprouts, and roots are eaten. The bier or rat-tail radishes are easy to grow and produce delicious pods that can be eaten raw or added to stir fry. Our favorite varieties here in north Florida are 'French Breakfast' and 'White Icicle' for fresh eating, 'Early Mino' for steaming (but we usually pick them young and eat them like salad radishes), and 'Munchen Bier' for the succulent pods which we use in salads and relish trays, and often eat right in the garden.
Many gardeners plant fast maturing radishes right in the same rows with slower maturing vegetables. The radishes germinate quickly to mark the rows, and are harvested before the other vegetables need the space.
Radishes are one of the easiest plants to grow. Salad radishes are the perfect vegetable for the youngest gardeners. From seed to table in about a month! Let a kid prepare the soil, plant the seeds, do the weeding, and bring in the crop! You'll create a gardener for life.
Create decorative radish roses by making several crisscross cuts from one end almost all the way to the other end, then soak in ice water for 30 minutes until the petals open.
Raw radishes contain large amounts of diatase, an enzyme that aids in the digestion of starches. Maybe that's why the Japanese always serve radishes with rice dishes, and the Europeans serve radishes with breads and breakfast cereals. Radishes contain many of the same anti-oxidants and cancer fighting compounds as other members of the crucifer family, such as broccoli, cabbage and kale.
Steve Christman 2/24/00; updated 8/18/03