code: 613
Cruciform flowers of bright purple open on compact
Family: Cruciferae
Common name: Koehler’s Rock Cress
Plant Classification: Hardy perennial
Minimum Height: 10 cm
Maximum Height: 20 cm
This very rare, tough, tufted endemic lives only on a few dry hills, high above the rushing Umpqua River on the Pacific coast of Oregon. Cruciform flowers of bright purple open on compact, rounded shrubby domes which cling tenaciously to the rocky outcrops. In 2001, to reduce chances of extinction, researchers grew hundreds of plants in the Berry Botanic Garden greenhouse using seeds collected from the wild. During the autumn rains, researchers battled the slippery slopes and clung to the steep cliffs to place plants and directly sow seeds into appropriate habitat near existing Koehler’s rockcress plants. Very few seeds available from cultivated plants.
Sowing advice:
Seeds can be sown at any time but are best sown in winter or early spring to benefit from a cold spell in the wet compost to break their dormancy. We advise covering seeds very thinly with sand or fine grit to about the depth of the seed size. If the seeds do not come up within 6 to 12 weeks the damp seed tray can be given cold treatment in a fridge for about four weeks. They may still take very many months to appear, so please never discard the pot or tray.
