About Rockcress: This alpine flower springs up in the high, barren mountain regions of most of Europe as well as Asia and North America. It naturally grows in moist, rocky ground or along streams and crevasses. Its foliage forms a dense mat close to the ground, while the stems support clusters of pure white, tiny flowers.
Rockcress Germination: Since this plant does not tolerate being transplanted, direct sowing is the best method. In late fall or early spring, sow the seed just below the surface in full sun or partial shade. Germination should take place within 14-21 days at 60-70 degrees F. Thin seedlings to 8-10" apart. Rockcress grows in almost any soil, and does especially well in dry or poor soil. Good drainage is essential.
Growing Rockcress Seeds: This plant does not need watering unless drought conditions persist. Though it tolerates some drought, high heat and humidity will have a damaging effect on rockcress. Since it spreads easily but does not become invasive, it makes an attractive native groundcover; it also grows well in rock gardens. After flowering, cut the stems back for attractive new growth. After two or three years of growing, divide the plant. Rockcress attracts butterflies and bees, and resists deer.
Harvesting Rockcress: For cut flowers, cut stems as soon as the blossoms open.
Saving Rockcress Seeds: After the flowers fade, the seed pods will form; they are long and thin, with many seeds in each pod. Remove them individually when they begin to turn brown, and spread them out to dry away from direct sunlight. Thresh them to separate the seed from the pods. Store the seed in a cool, dry place.
Detailed Rockcress Info: Origin: US Native Other Common Names: Alpine Rockcress Duration: Perennial Bloom Time: Spring Height: 8-10 inches Spacing: 15-18 inches Light: Full Sun to Part Shade Soil Moisture: Dry USDA Zone: 4-8 Seeds Per Oz: 95,000 Produces a plant with a rosette of oval, serrated leaves at the base and a loose cluster of four-petaled white flowers at the top of each stem.