Summer Flower Gallery. Gaura (Gaura lindheimeri), is an herbaceous perennial that grows in a loose, bushy clump 2-4 ft (0.6-1.2 m) tall with a spread of 2-3 ft (0.6-0.9 m). The individual flowers are about an inch across and have four reflexed petals. They are white when they open at dawn, fading to rose-pink by the end of the day.