Selaginella kraussiana aka Garden Selaginella

Selaginella kraussiana is an evergreen perennial in the Selaginellaceae family. Gardeners call it mat spike moss or trailing clubmoss. It comes from Macaronesia and tropical and southern Africa. Its native climate is wet and tropical. Despite its moss-like look, it is a vascular plant. It has true roots and shares ties with ferns. It is not native to Britain or Ireland.

This plant creeps across the ground and forms dense mats. Its stems take root as they spread over the soil. Garden height is about 0.16–0.33 feet [0.05–0.1 metres]. Sources give quite different widths for plants in cultivation. NC State lists 1–1.5 feet [0.3–0.46 metres]. The RHS gives 3.3–4.9 feet [1–1.5 metres]. Growth is fast, with maturity reached in one to two years. Small, green, scale-like leaves give it a fine, fern-like texture. The foliage feels soft and has no hairs. This species has no flowers, and growers can propagate it from spores.

Grow it in shade, with rich soil that drains well. It suits acid or neutral soil and needs steady moisture. High humidity helps the leaves stay in good shape. Indoors, give it bright light filtered from direct sun. Its shallow roots suit shallow pots with good drainage. The RHS recommends loam-based, peat-free compost mixed with leafmould under glass. Use two parts compost to one part leafmould. Protect it from frost in cold climates. The RHS rates it H2 and recommends winter temperatures of 5–7°C. Chicago Botanic Garden lists USDA zones 9–13. NC State gives the narrower range of zones 11–12.

Use it in pots, dish gardens, terrariums, or bottle gardens. In warm climates, it can cover soil in shaded gardens. It also suits shaded rock gardens and woodland settings. Its dense growth can serve as a lawn substitute. It tolerates light foot traffic and resists rabbit browsing. Trimming can limit its spread, though routine pruning is not needed. Root stem cuttings in damp soil, or divide rooted stems in spring.

Direct sun can burn the leaves. Dry air can make them turn brown or shrivel. Soil that stays wet can cause root rot. The RHS reports few disease problems overall. ASPCA lists it as non-toxic to dogs, cats, and horses. That safety rating does not establish that people can eat it.