Aubrieta deltoidea
purple rock cress
Eastern Mediterranean and southwestern Asia
Overview
Aubrieta deltoidea is a low, mat-forming evergreen perennial in the cabbage family, spreading into dense cushions 2-6 inches (5-15 cm) high and 12-24 inches (30-60 cm) wide. The small, grey-green leaves are spoon-shaped to diamond-shaped, 0.4-0.8 inch (1-2 cm) long, with a few coarse teeth and a covering of short hairs. In spring the mat is blanketed in four-petaled cross-shaped flowers 0.5-0.8 inch (12-20 mm) across, in shades of violet, purple, mauve, and rose. The flowers nearly hide the foliage at peak bloom and draw early bees and butterflies. After flowering the plant can grow leggy and open at the center. It roots as it spreads, cascading over walls and rocks and knitting between paving. Native to the eastern Mediterranean and southwestern Asia, it grows wild on rocky slopes and cliffs and is widely cultivated in rock gardens. It needs sharp drainage and full sun, tolerating drought, lime, and poor stony soils, but it rots in heavy, wet ground and is short-lived where summers are hot and humid.
Native Range
Native to the eastern Mediterranean and southwestern Asia, including Greece, Turkey, and the Balkans, where it grows on limestone cliffs, rocky slopes, and scree. It has naturalized on old walls and rocky banks in temperate Europe after long garden use.Suggested Uses
Grown in rock gardens, on dry stone walls, along path edges, and in the gaps of paving and steps where it can trail and cascade. It pairs with other spring alpines and bulbs in sunny, well-drained rock plantings.How to Identify
Appearance
Size & Dimensions
Height2" - 6"
Width/Spread1' - 2'
Reaches mature size in approximately 2 years
Bloom Information
Blooms heavily in mid to late spring, generally April to May, covering the foliage for four to six weeks. A lighter second flush can follow in autumn in cooler climates. Shearing the plant right after the main bloom keeps it compact and can prompt repeat flowering.
Detailed Descriptions
Flower Description
violet to purpleFoliage Description
grey-greenGrowing Conditions
Sun Requirements
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Grows in full sun in gritty, sharply drained, neutral to alkaline soil, including poor and stony ground. It withstands drought, heat at the root, and exposure once established, but waterlogged or rich soil causes rot and floppy growth. Shearing the mat back by about a third after flowering keeps it dense and prevents bare centers. It is short-lived in hot, humid summers and performs longest in cool-summer regions with mild winters. Plants are easily renewed from cuttings or by division of rooted stems.Pruning
Shearing the whole mat back by one-third to one-half immediately after the spring bloom keeps it compact and encourages fresh growth. Without this cut the plant grows woody and opens at the center. No other pruning is required.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
late springsummer
Container Growing
✓ Suitable for container growing
Minimum container size: 1 gallons