Blackberries are a purple-black fruit, oblong in shape, growing up to 1 1/2inches in length. They are semi-soft and, depending on variety, range from tart to sweet in flavor and usually contain seeds.
Due to a wide range of growing areas, blackberries are available year round. True peak season is late spring through summer. Blackberries grown out of season are no match in flavor or texture for the seasonal farmers market type of berry.