Asperula, Genus, spp., Multiple species,
- Genus
- Multiple species
Europe, the Mediterranean, western Asia, and Australia
Overview
Asperula is a genus of about 200 annual and perennial herbs in the madder family, found across Europe, the Mediterranean, western Asia, and Australia. Most are low, tufted or mat-forming plants 2-18 inches (5-45 cm) tall with slender stems bearing narrow leaves in whorls of four to eight, in the manner of bedstraws. Small tubular flowers with four spreading lobes, about 0.1-0.3 inch (3-8 mm) long, open in clusters in late spring and summer, white, pink, or pale blue depending on species. Alpine species such as A. arcadiensis form silver-haired cushions with pink flowers, while A. tinctoria, dyer's woodruff, has white flowers and roots once used for red dye. Foliage of the fragrant species smells of fresh hay when dried, from coumarin in the leaves. Mat-forming species spread by slender rhizomes to form low patches, and some sprawl loosely among neighbours. Cushion alpines are short-lived in wet or heavy soil and may rot over winter.
Native Range
Native to Europe, the Mediterranean region, western and central Asia, and Australia. Grows on rocky alpine slopes, dry grassland, scrub, and open woodland, with cushion species on stony mountain ground and woodland species in shadier sites.Suggested Uses
Grown in rock gardens, troughs, raised alpine beds, and gravel gardens, with cushion species spaced 6-10 inches (15-25 cm) apart. Woodland species are used as low groundcover in dappled shade. Cushion alpines grow in containers of at least 1 gallon (4 L) with a gritty, free-draining mix.How to Identify
Appearance
Size & Dimensions
Height2" - 1'6"
Width/Spread6" - 1'6"
Bloom Information
Detailed Descriptions
Flower Description
white, pink, or pale blueFoliage Description
green to silver-hairedGrowing Conditions
Sun Requirements
Requires 4-10 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
Cushion and alpine species grow in full sun and gritty, sharply drained soil, while woodland species take part shade and moister ground. Wet, heavy soil rots the silver-haired alpines, especially over winter. Plants are watered sparingly once established, as most tolerate dry conditions. Few pests trouble the foliage. Mat-forming species spread by rhizome and are divided in spring to renew them or limit their spread. Foliage of fragrant species contains coumarin, which scents the dried leaves and can harm pets in large amounts.Pruning
Plants are sheared lightly after flowering to keep cushions and mats compact. Spent stems of taller species are cut back in autumn. Spreading rhizomatous species are divided or edged in spring to control their extent.Pruning Schedule
summerfall
Container Growing
Suitable for container growing
Minimum container size: 1 gallons
