Dig up red turnips in the spring if they were planted in late winter or just after the first frost if they were planted in late summer. Wait until the tops of the roots are uniformly red in color before digging them up.
Measure out 5 inches from the row of red turnips. Insert the tines of a spade fork 12 inches deep into the soil. Pull the handle of the fork back toward your body to pry the roots from the ground.
Crumble off all the soil or mud that is stuck to the red turnips. Scrub them with a dry scrub brush to take off as much soil as possible. Cut off the greens using a pair of pruning shears.
Store the red turnips in a breathable cloth bag such as a gunny sack. Place them in a cool, dry place away from direct sunlight or excessive humidity. Use them within six months.