1990 Perennial Plant Association's Plant of the Year. Need a bold shot of color to herald spring's arrival? Creeping Phlox are an invaluable addition to any rock garden, foundation, or as an edger or groundcover. Blanketed in soft lilac shades, Phlox Sherwood Purple is an attractive shade grower, either alone or as a groundcover. The plants spread laterally along the ground with masses of carefree flowers on short erect stems.