Abstract: A durable, modular, adaptive containment system, which has a composite composition comprised of wood fibers embedded in a polymeric matrix, the system being suitable for holding soil and plants, and which is comprised of rails, preferably of rectangular cross-section, each of said rails being joined by means of a T-shaped tenon along one of its ends and a complementary T-shaped channel on the side of the rail near its other end, or which is comprised of a connector having T-shaped channels so that when four rails, each of which has a T-shaped tenon on each end, pairs of which are of equal length, are joined by inserting the T-shaped tenons of each rail into a complementary T-shaped channel on a connector, a rectangular containment system is formed.