We were given this plant by the late Art Dome and don't know if it is Cassiope lycopodioides var. gracilis or Cassiope mertensiana var. gracilis - (we suspect mertensiana). White 'Lily of the Valley' type flowers on a vigorous, upright shrub.  Grows to about 8" x 12".  An exceptionally rare alpine plant.  Needs protection from the hot afternoon sun.  A key to success is keeping the roots cool in the afternoon.  They need good drainage as well.