The turnip or white turnip is a root vegetable commonly grown in temperate climates worldwide for its white, fleshy taproot. The word turnip is a compound of turn as in turned/rounded on a lathe and neep, derived from Latin napus, the word for the plant.
Add plenty of well rotted compost or manure to the beds and cultivate to a depth of 20cm (8″). Dig in 1 cup of complete organic fertilizer for every 3m (10′) of row. The real secret to success with turnips is speed. Sow short rows every 2-3 weeks, thin them quickly, keep them watered, harvest, and then sow some more.