Turnips are Cool Season Vegetables from the Cabbage Family (Brassica rapa var. rapa from Brassicaceae Family). The plant is not native to North America. Not known in the wild. Probably developed in cooler parts of Europe.
How plant turnips
Propagate by seed. Will germinate at soil temperatures as low as 40 F. Days to emergence: 4 to 7.
From early spring to late summer, sow seeds ¼ to ½ inch deep, 1 inch apart in rows 12 to 18 inches apart. Thin plants to 4- to 6-inch spacings. Plant thickly, and once the plants are 4-6 inches tall, start thinning them by hand.
Plant every 2 weeks for continuous harvest.
Needs plentiful, consistent moisture. Loosen soil deeply or grow in raised beds to encourage good root development.
When to plant turnips
Turnips are a cool-weather crop. Plant them early in the spring as soon as the ground can be worked, and again plant toward the end of summer for a fall crop.
Caution: Some varieties are grown strictly for their greens and produce poor quality roots.
Good turnip varieties:
Purple Top White Globe
Gardening Articles :: Edibles :: Vegetables :: National Gardening Association http://goo.gl/P65iO
Explore Cornell - Home Gardening - Vegetable Growing Guides - Growing Guide http://goo.gl/VxoyL
Turnips & Rutabagas - Gardening Articles :: Edibles :: Vegetables :: National Gardening Association - http://goo.gl/lhfcw