Arborvitae Fern, though it produces spores is not a true fern but a prehistoric plant called a club moss. Its thick scaly leaves, that resemble Arborvitae or Cedar, form a matting groundcover quickly shading out weeds. Grows in partial shade to shade, in well-drained, organically enriched soil. Though it likes shady moist spots, it does not withstand standing water. After a harsh winter if fronds appear ragged cut it back, apply an all purpose slow-release fertilizer, and new growth will appear quickly. The clumps can be divided any time of year or cutting root easily in damp soil.