(Buxus sempervirens) Evergreen. Pungent, deep green, shiny foliage that forms a dense screen on mature plants. Leaves are dark green, and rounded, and are light or yellowish green on undersides than tops ( 1/2 to 1" long, about 1/2 as wide ). Leaves are lustrous on both sides. Tiny , inconspicuous flowers open in midspring. Outstanding for hedges and topiary gardens. Growth rate is slow. Sometimes called the aristocrat of hedging plants. Protect from wind and sun in cold winter areas, as they may burn leaves. Will assume a treelike habit of growth if it is not clipped. 25 feet max. Tree Box ( Sempervirens arborescens ) - 30 feet.