Clematis 'Marie Boisselot', a vigorous deciduous climber, grows 8 to 10 feet and produces large, single, creamy white, 6 to 8-inch flowers with yellow centers in early summer to early fall. It flowers on old wood in the spring and then again on the new season's growth and is a member of clematis pruning group 2 or 3. A hard pruning in the late winter to early spring will delay flowering until the fall. It is attractive grown through and over low-growing conifers or medium-size shrubs or as a partner to climbing roses.