Hard red spring wheat flour is named for its berries, which are closely related to hard red winter wheat. Planted in spring and harvested in the fall, hard red spring wheat has the highest protein content of all the wheat varieties (13.5%). Many bakers will add this to flour made from softer wheat for the extra protein content it imparts to the bread. Like hard red winter wheat, hard red spring wheat has a reddish colored husk and produces a slightly darker flour than a white wheat. Spring wheat tends to have more gluten content than the more common winter wheat varieties.