Although small, the leaves of lupinus concinnus
are quite distinctive as they are densely covered by white hairs, which are almost as long as the width of the leaflet; leaves are divided into 5 to 9 linear to oblanceolate leaflets, each around an inch in length. The stems and calyces are similarly hairy. Leaflets may fold up along the axis.
Flowers have the familiar pea shape, formed of five petals, all of which have the darkest coloration around the edge. The two wing petals and the two fused keel petals are pink to purple, while the upper (banner) is pale cream to white - either all over, or just at the center, surrounded by the pink/purple. The cream/white patch is flecked with purple dots. The keel is usually hairless. Flowers form as small elongated clusters, covering just a few inches at the top of the short, reddish stems (and sometimes from the upper leaf nodes), which grow upwards or at an angle. Fruits are broad, flattened, straight pods, up to half an inch long, with a moderate hair covering, colored dark green, often blackish along the edges.