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Brownstem Spleenwort

Asplenium platyneuron (ah-SPLEE-nee-um pla-tee-NUR-on)

Family: Aspleniaceae Native Herbaceous (1-3 ft)

Ebony Spleenwort is a diminutive evergreen fern in the Spleenwort family (Aspleniaceae). It has a surprising natural distribution, being native to both South Africa and eastern North America. It grows in a broad range of habitats such as rocky banks and outcrops, disturbed sites, fields and wooded slopes. The species epithet means flat or broad nerve and refers to the prominent central vein on young, undivided fronds. This fern grows best in well-drained, rocky soils, in shade to part sun, with dry to medium moisture. It is not sensitive to pH but prefers acidic conditions with a pH of 4.5 to 5. It is characterized by its dimorphic fronds. Sterile evergreen fronds are lighter green, glossy, slightly arching or may lay close to or flat on the ground. Fertile deciduous fronds are erect, dark green and die off in the winter. The central stem (stipe) is dark brown (and the source of the common name). Ebony Spleenwort reproduces by spores and vegetatively by forming buds near the base of the base either sterile or fertile fronds. Pale button-like buds appear on the upper side of the lowest leaflets. When buds fall off and contact soil, they produce new ferns as the parent plant dies off. The upright form of the fertile fronds ensures efficient spore dispersal by wind. This fern is known to hybridize naturally with other species, producing sterile offspring. Some Canadian Provinces and U.S. states consider this plant a vulnerable or endangered species. It is easy to grow and suitable for woodland or native plant gardens in dry, rocky, shady crevices. Shade or woodland gardens are appropriate settings. Insects, Diseases, and other Plant Problems : This fern has no major diseases but is susceptible to slugs and black fern aphid. If conditions remain too wet, it may be susceptible to crown rot. VIDEO Created by NC State Extension's Homegrown series featuring Mark Weathington , Director of JC Raulston Arboretum .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 42 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (1-3 ft) Optimal soil pH Acid (<6.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Full plant profile

Growing Conditions
Plant type
Fern; Herbaceous Perennial; Native Plant
Life cycle
Perennial
USDA zones
3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Dappled Sunlight (Shade through upper canopy all day) | Deep shade (Less than 2 hours to no direct sunlight) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
High Organic Matter; Loam (Silt); Shallow Rocky
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage | Moist | Occasionally Dry
Available space
12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 0 ft. 8 in. - 1 ft. 8 in. | Width: 0 ft. 8 in. - 1 ft. 8 in.
Maintenance
Low
Canopy layer
4 - Herbaceous (1-3 ft)
Form & Appearance
Habit / form
Arching; Clumping; Rounded
Texture
Fine
Leaf color
Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately); Fronds
Leaf arrangement
Alternate
Leaf shape
Linear; Oblanceolate
Leaf margin
Crenate; Serrate
Leaf size
> 6 inches long, 1-3 inches wide
Hairs present
Yes
Leaf detail
Slender, sterile, lighter-green, evergreen fronds are arching to flattened. Erect, dark green, deciduous fertile fronds whither in winter. Fronds taper at both ends. Fronds are blade-shaped, linear or oblanceolate, and wider at the upper half of the blade. The blades are shiny, pointed at the tip, tapered near the base and may have a few hairs. Each blade is cut into leaflets (pinnae) along its length (15-45 pairs), alternately arranged on rachis. Leaflets are oblong, each with an auricle at the base pointing toward the tip of the blade. Undersides may have minute scales. Edges are crenate or serrulate. Blades reach lengths of 20 inches and widths of 0.8-3 inches. Leaflets are 0.4-1 inch long. Leaflets have up to 18 pairs of sori on the underside, each 0.04-0.08 inches in size. Each pair points toward the base of the leaflet in a herringbone fashion. Buds form at the base of the stipe on sterile and/or fertile fronds, and sprout into new ferns when they contact soil.
Flower detail
No flowers
Fruit detail
This plant has no fruits. It reproduces via spores and vegetatively.
Stem color
Black; Brown/Copper
Stem detail
Shiny, dark stems and axis
Wildlife & Ecology
Native status
Native
Origin
North America E. of Rocky Mts., S. Africa
Distribution
North America E. of Rocky Mts., S. Africa
Play value
Easy to Grow
Landscape Use
Landscape theme
Shade Garden
Garden tags
#evergreen #food source fall #food source summer #food source herbage #FACU Piedmont Mountains #Audubon #fern #deer resistant #shade garden #Coastal FACU #NC native
Problems & Resistance
Resistant to
Deer; Heavy Shade
Particularly resistant to
Deer, Heavy Shade

Planted at Hunnicutt

Nobody’s planted this one yet.