Petrorhagia (Petrorhagia Saxifraga)

Features and Characteristics

Petrorhagia saxifrage, commonly called tunic flower, coat flower, tunic saxifrage or pink saxifrage, is a spreading, mat-forming, grass-like perennial of the pink family. It is native to rocky, sandy, limy soils in the Pyrenees, southern to central Europe and Turkey. It has been introduced into North America where it has naturalized over time, primarily into fields, meadows and disturbed soils in Quebec, Ontario and the eastern and central U.S. north of USDA Zone 8. It is noted for producing a spreading foliage mat of short, narrow, grass-like, linear, pointed green leaves rising to only 4” tall but spreading over time to as much as 18” wide. Thin, wiry flower stems rise in spring above the foliage mat to 8-12” tall. Stems are topped by small dianthus-like, 5-petaled white flowers (to 1/2” wide) which bloom from spring into summer in loose clusters or solitary. Spring flowers are white, but summer flowers usually have pinkish tones. When flowering stops, plants may be cut back to encourage an additional bloom that may last into fall.

Formerly known as Tunica saxifrage, Dianthus saxifrage, and Dianthus filiformis.

Genus name comes from the Greek petros meaning rock and rhagas meaning narrow opening or fissure in reference to this plant’s ability to live in the cracks of walls.

Specific epithet literally means stone-breaker (from Latin saxum meaning rock and frangere meaning to break) in reference to this plant’s ability to live in rock crevices.