Very hardy heirloom with a delicious flavor. A primitive broccoli strain that produces small purple heads and many offshoots. Plant produces once overwintered. Great for broccoli sprouts. As shown on the table, a 100 gram serving of raw broccoli provides 34 kcal and is an excellent source (20% or higher of the Daily Value, DV) of vitamin C and vitamin K. Raw broccoli also contains moderate amounts (10–19% DV) of several B vitamins and the dietary mineral manganese, whereas other essential nutrients are in low content. Broccoli has low content of carbohydrates, protein, fat, and dietary fiber. Boiling broccoli reduces the levels of sulforaphane, with losses of 20–30% after five minutes, 40–50% after ten minutes, and 77% after thirty minutes. However, other preparation methods such as steaming, microwaving, and stir frying had no significant effect on the compounds.