How to plant Aubretia
Aubrieta deltoidea, also known as rockcress and lilacbush, is a clump-forming groundcover that produces small purple flowers with yellow centres in early spring. This plant performs very well in a rock garden, where it will take advantage of the sandy, rocky soil and cascade beautifully over the rocks.
Choose a site in full sun. This plant will tolerate partial shade, but a well-draining site in full sun is best.
Plant transplants in holes as deep as the root ball in the package. Tamp down the soil after planting.
Space plants 30 to 60 cm (12 to 24 inches) apart, as full-grown plants range from 30 to 60 cm (1 to 2 feet) wide and you'll want to give Aubrieta room to spread out.
Water the transplants well. This plant will need regular watering for its first year, but after it is established it is fairly drought tolerant and should receive 2.5 cm (1 inch) of water per week when rain is scarce.
Cut back the plant drastically once flowers begin to fade. This will encourage a second bloom.