A classification of some crop varieties, especially soybeans, based on their growth and development. For example, a soybean with maturity group O or OO only needs a short growing season before harvest; whereas, a soybean with maturity group V and VI needs a longer growing season before the plant is completely developed and ready for harvest. There are 13 soybean maturity groups, i.e., OOO, OO, O, I, II, III, IV, V, VI, VII, VIII, IX, and X. Maturity groups are also described in the context of their indeterminate / determinate growth habit.