Polytrichum commune aka Jensen's Polytrichum Moss

Polytrichum commune is an evergreen moss in the family Polytrichaceae. Its common names include common haircap and great golden maidenhair. It grows across the Northern Hemisphere's temperate and boreal regions. Its range also includes Mexico, Australia, and several Pacific islands. New Zealand is among the islands listed in its range. It grows in bogs, wet heathland, and beside forest streams. These habitats reflect its need for a steady supply of moisture.

This perennial forms clumps that join into a low carpet. Its growth is slow, but its mats can spread without a fixed limit. Plants For A Future gives a height of about 0.7 feet [0.2 metres]. It lists a spread of about 1 foot [0.3 metres]. That width is not a firm limit for an established mat. The evergreen growth provides cover through the year. Its low form suits ground cover rather than a tall planting. The supplied sources give no further details about leaves or stems.

Choose a damp site with light shade for cultivation. It also grows in deep shade or in full sun. In sun, the soil must stay moist. It prefers moist to wet ground and accepts slow drainage. Slightly acidic soil suits it, though it also tolerates stronger acidity. It grows in sandy, loamy, and clay soils. Poor soil does not rule out a suitable planting site. Plants For A Future lists USDA hardiness zones 2–10. It also gives a UK zone of 3, without an RHS hardiness code.

The moss has value as ground cover in damp, shaded gardens. Its mats can cover soil where these growing conditions suit it. Plants For A Future also records several uses beyond the garden. People have woven the stems into baskets. A rinse made from the plant has been used for hair. The source reports tea use for kidney and gall bladder stones. This records a traditional use, not proof of medical benefit.

The source lists no known edible uses and no known hazards. That does not establish that eating it is safe. It reports no weed potential. The supplied evidence names no pests or diseases. Propagation uses spores, which wind carries away during summer. This seasonal spore release is not a flowering period.