Harvesting: Enjoy purple kohlrabi sprouts when they have small, green leaves, usually 6 to 8 days after starting. Some sprouting seeds have hulls (the outer seed covering), which can loosen during soaking and rinsing. Although the hulls are edible, you may choose to remove them for better sprout flavor, or to reduce the chance of mold due to excess moisture. To separate the hulls, empty your sprouts into a large bowl and fill it with cool water. Move the sprouts around in the water disentangling the sprouts and loosening the hulls, which will float to the top. The hulls can then be skimmed or poured off. Remove any unsprouted seeds at this time, too. Rinse the sprouts once more and drain thoroughly so they are dry to the touch. (Excessive moisture reduces sprouts' storage life.) Your sprouts are then ready to eat or store.