Cassiope lycopodioides x C. fastigiata - White 'Lily of the Valley' type flowers on  thin, well branched stems.  It is a reliable bloomer.  Grows to about 6" tall x 12" wide. A choice and 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.