With parents like Hosta 'Sum and Substance' x Hosta montana var. macrophylla, you know the results are going to be something special. The 3' wide upright vase-shaped clump is composed of long thick chartreuse-green leaves and topped in late summer with 3' tall spikes of white flowers. For added interest, the shiny foliage is also deeply ribbed as well as ruffled along the edges. A mature clump of Hosta 'Grand Canyon' does indeed do justice to the infamous landmark.