4-6" tall x 15-18" wide. Prairie Phlox (Phlox villosissima) is a wide-ranging native species that blooms in late spring with hundreds of fragrant, bright pink flowers. Use this perennial as a groundcover for harsh, poor soil growing sites where it suckers to form colonies of low growing plants. Our selection (previously known as Phlox pilosa ssp. riparia) hails from central TX and is an excellent choice for areas with hot, humid summers.