965 Brassica rapa var. rapiferaCommon Names: turnip Family: Brassicaceae (cabbage Family)
The turnip is a biennial (typically grows for one season, overwinters, and then flowers in the next season) that is grown as an annual. The leafy stems may get 1-2 ft (0.3-0.6 m) tall and the below ground "root", an inch to as much as a foot in diameter. (To be strictly correct botanically, we should note that the turnip's "root" is not a root at all, but rather the swollen stem of the plant.)
Different varieties of turnips have been developed for their edible roots, their edible leaves and for both. The old standards for American gardeners are 'Purple Top White Globe' for the roots, and 'Seven Top' for the greens. But there are some 40 different cultivars available from American seed catalogs (see Cornucopia II for descriptions). There are turnips with red, green, yellow or white skins; with white or yellow flesh; and turnips shaped like globes, flattened globes, carrots, eggs, or spindles. The modern hybrid, 'Oasis' produces a small, sweet and tasty pure white turnip in a very short season. The heirloom, 'Gillfeather', developed in Vermont in the late 1800's, has a mild, sweet flavor that stays good even when it gets big.
The turnip is one of the oldest vegetables cultivated by Man. Evidence of turnip cultivation dates at least to 4000 years ago. The lowly turnip is not very popular in America, but it's an important food in most of the rest of the non-tropical world, even if some gastronomical snobs consider it a food only for poor people and livestock. Although its ancestor is no longer known, turnips were apparently first developed in central Europe from some species of wild Brassica. Turnips were introduced to North America in the late 1500's.
CultureTurnips are easy to grow in almost any soil, as long as it isn't too wet or too hard. Acidic soils should be limed to a near neutral pH. Light: Full sun is best. Moisture: Water your turnip crop deeply with about an inch of water each week. Erratic watering or more frequent shallow watering may cause the turnips to bolt to flowering prematurely before they develop a decent root. Hardiness: USDA Zones 3 - 10. Turnips are among those most cold tolerant of vegetables, almost as hardy as rutabagas. They can tolerate frost and moderate freezes, but temperatures below 10 or 15º F ( -9.4 º C) will top-kill most turnip plants. Propagation: Turnips are cool weather crops, planted in very early spring - even before the last frost, or in late summer so they will mature during the cool weather of autumn. In much of northern North America, turnips are planted in July or August. In the deep south, turnips are grown in the winter; in zones 8 and 9 turnip seeds are planted in September, October or November. Sow turnip seed rather thickly, covering with about a quarter inch of soil and water well. Germination takes less than a week. If you're growing turnips for the roots, thin the seedlings to about 6 in (15 cm) apart when they are 3-6 in (7-15 cm) tall. (Eat the little seedlings raw in salads or steam like spinach.) If you're only interested in the greens, thin by harvesting.
Turnips are best when grown fast and picked young, especially those planted in spring. As the weather warms, the greens become bitter and the roots become woody and stringy. Fall and winter crops are more dependable and usually produce sweeter turnips. Winter grown turnips will remain in good condition as long as the weather stays cool. It seems that frost improves the flavor of turnips. Turnip greens are ready to harvest in just 5-7 weeks. Take a few leaves from each plant - don't pull up the whole plant, and it will grow new leaves and continue to develop the root. The roots will be at their peak in a few more weeks. Leave turnips in the ground until you need them as long as the weather stays cool and the ground doesn't freeze solid. If you must pick more than you need, the roots keep well for a few weeks in the refrigerator and the greens can be frozen like spinach.
Turnip greens are popular in the American South; they are cooked like spinach, sometimes with the roots chopped up and mixed in with the greens. Served with vinegar or tabasco sauce, or with butter and salt and pepper, turnip greens are a favorite around this household. But, please don't overcook them! And don't forget the cornbread! We also use turnip greens in stir fry - added at the very last minute, of course. Fresh young turnip roots are excellent sliced and served raw like kohlrabi or radishes. Most varieties of turnips are at their best when only 2-3 in (5-8 cm) in diameter. Use the larger roots boiled and mashed like potatoes, or cooked in stews or soups. In much of Asia and the Middle East, turnips are pickled. The Japanese carve raw turnips into intricate flower shapes. The Chinese sun dry turnips or preserve turnip strips in soy sauce.
See Floridata's mustard greens profile for a partial list of the edible and cultivated species in the genus Brassica. Turnips are classified in the Rapifera Group of Brassica rapa, a species that also includes pak choi (Chinensis Group); Chinese cabbage and celery cabbage (Pekinensis Group); Tendergreen or mustard-spinach (Perviridis Group); and broccoli raab (Ruvo Group).
Steve Christman 12/08/02, 05/29/03