Snowball Turnip doesn"™t cross-fertilize with Brassica oleracea, head cabbage, kale, broccoli etc, however, easily with Chinese leaves, turnips, wild field turnip and sometimes even with swede. Seed of "snowball" turnip is grown in the same way as the normal turnip, but could also be treated as an annual and in that case it must be sown as early as possible. Remove any roots that are not up to the sort standard. Set out the roots with 30 cm of mutual space. "Snowball" Turnip that are to be stored in a cellar, to be set out next spring should be sown in July and if they are to remain in the plot and covered during winter they should be sown even later in Aug.-Sep.
Half-grown roots cope best with winter. The seed harvest is the same as with the other cabbage plants. Read further under "Growing cabbage plants". Be extra careful when harvesting, the ripe seeds sit loosely and tumble off easily.