Eriophorum angustifolium

Perennial of the Cyperaceae family, the narrow-leaved cotton-grass is widely spread in the boreal and cold temperate zones of the northern hemisphere: Europe, Northern Asia, and North America. It colonizes bogs, acidic marshes, lake edges, and marshy meadows, from plains to subalpine levels, on poor, acidic, and constantly waterlogged substrates.

It forms upright clumps of 20 to 60 cm, spreading by underground stolons and often forming vast colonies. The leaves are linear, narrow, grooved, and bright green. The triangular stems bear several spikelets whose perianth bristles lengthen considerably after flowering to form long, pure white cottony tufts, carried by drooping peduncles — it is this fruiting stage that gives the plant its character, the tufts quivering at the slightest breath of wind like so many small suspended flakes.

In its natural habitat, it blooms from April to June, with cottony tufts persisting until July-August. The bristles were once harvested to stuff cushions and mattresses in northern regions.

In cultivation, it requires an acidic, constantly moist to waterlogged soil, in full sun or partial shade; it is perfectly suited to bank gardens and peat-substrate ponds.