Eriophorum vaginatum
tussock cottongrass
Northern Europe, northern Asia, and North America
Container Friendly
Native to North America
Overview
Eriophorum vaginatum is a tufted perennial sedge that forms dense, raised tussocks 1-2 feet (30-60 cm) tall in acid bogs and wet moorland. The narrow, wiry leaves are three-sided and channeled, dying back to form the firm base of the tussock that can persist for decades. In early spring single erect flowering stems carry a tight head that, after flowering, expands into a rounded tuft of white cottony bristles about 1-1.5 inches (2.5-4 cm) long, resembling a ball of cotton wool. These cotton heads aid wind dispersal of the small seeds. The plant is among the first to flower on open moorland, often before the surrounding vegetation greens up. It grows in waterlogged, nutrient-poor, strongly acid peat. A limitation in cultivation is its strict need for permanently wet, acid, low-nutrient ground, which makes it unsuited to ordinary garden soil.
Native Range
Eriophorum vaginatum is native to the cool temperate and subarctic regions of the Northern Hemisphere, across northern Europe, northern Asia, and North America. It is a characteristic plant of blanket bog, raised bog, and wet acid moorland.Suggested Uses
Eriophorum vaginatum is used in bog gardens, acid wetland restoration, and naturalistic pool margins with permanently wet, acid soil. Its early cotton heads give seasonal interest in spring and early summer. It supports the specialized insects and birds of peatland habitats.How to Identify
Appearance
Size & Dimensions
Height1' - 2'
Width/Spread1' - 1'6"
Bloom Information
Flowering occurs in early to mid spring, often April, when the inconspicuous flower heads open before the cotton develops. The white cottony seed heads expand from late spring into early summer. The cotton persists for several weeks before the seeds are shed.
Detailed Descriptions
Foliage Description
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
Eriophorum vaginatum grows in full sun in permanently wet, acid, nutrient-poor peat, tolerating a soil pH from about 3.5 to 5.5. It needs constant moisture and will not survive where the ground dries out or where soils are limy or fertile. The plant forms slowly building tussocks and spreads mainly by seed rather than by runners. It requires no feeding, as added nutrients favor competing plants. Growth is slow, and tussocks may take years to reach full size. In gardens it is limited to bog gardens and acid pool margins that mimic its native conditions.Pruning
No pruning is required. Old foliage can be left to build the tussock or trimmed back in late winter if a tidier clump is wanted. Spent cotton heads are removed to limit self-seeding where this is not desired.Container Growing
✓ Suitable for container growing
Minimum container size: 3 gallons