Selaginella braunii belongs to one of the oldest lineages of vascular plants on Earth, a group of club mosses that predates flowering plants by hundreds of millions of years. Despite the common names Arborvitae Fern and Chinese Lace Fern, it is neither a fern nor a flowering plant but a spikemoss, reproducing by spores and building its flat, finely divided fronds in a way that strongly echoes the scale-like foliage of arborvitae or cedar. In zones 6 through 9, it forms an evergreen mat six to eighteen inches tall, spreading steadily to cover ground and shade out competing weeds in partial to full shade.

Arborvitae Spikemoss prefers organically enriched, well-drained soil and consistent moisture, but it will not tolerate standing water around its base. The plant excels as a living skirt around the base of taller container plants, as a terrarium subject in smaller varieties, or as a shaded border filler. After a particularly harsh winter, ragged fronds can be cut back hard; an application of slow-release fertilizer prompts fresh, tidy growth in short order. Clumps divide readily at any season, and cuttings root in damp soil without fuss.