Polypodium virginianum
rock polypody
Overview
Polypodium virginianum is a small, evergreen fern 4-12 in (10-30 cm) tall, forming spreading mats from a slender, creeping rhizome that clings to rock. The leathery, deep green fronds are 4-10 in (10-25 cm) long and pinnately divided nearly to the midrib into 10-20 pairs of blunt, oblong segments. The fronds are evergreen, lasting through winter, with new fronds unrolling in spring and early summer. On the undersides of fertile fronds, round orange-brown spore clusters (sori) sit in two rows, one on each side of the segment midvein. The fern reproduces by spores and by the spreading rhizome, forming colonies over rock surfaces. It grows on shaded boulders, cliff ledges, and rocky banks, usually on acidic rock, across eastern North America. It tolerates short dry spells by curling its fronds but needs shade and a moist, humus-filled crevice to establish, and grows slowly.
Native Range
Native to eastern North America, from eastern Canada south through the Appalachians and Midwest, where it grows on shaded acidic rocks, boulders, cliffs, and rocky slopes.Suggested Uses
Grown in shaded rock gardens, on stone walls, boulders, and in crevices, and in woodland gardens with acidic rock. It works as a slow evergreen groundcover over shaded stone where little else roots.How to Identify
Appearance
Size & Dimensions
Height4" - 1'
Width/Spread1' - 2'
Bloom Information
Ferns do not flower. New fronds unroll in spring and early summer, and spores ripen in the round sori on fertile fronds from late summer into autumn. The evergreen fronds persist through winter until replaced the following year.
Detailed Descriptions
Foliage Description
dark greenGrowing Conditions
Sun Requirements
Tolerates up to 4 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Polypodium virginianum grows in part to full shade on moist, acidic, humus-rich pockets among rocks, and suits shaded rock gardens, stone walls, and crevices. It needs sharp drainage and steady humidity rather than wet soil, and rots in heavy, waterlogged ground. The creeping rhizomes are laid on the surface and pinned among rocks or mossy crevices to establish. Once settled, the fern spreads slowly and needs little care beyond a mulch of leaf litter. It tolerates brief drought by curling its fronds, recovering when moisture returns.Pruning
No routine pruning is required. Damaged or winter-worn fronds are removed in spring as new fronds emerge. The plant is otherwise left undisturbed to spread over rock.Container Growing
✓ Suitable for container growing
Minimum container size: 1 gallons