Description
Gymnocarpium –
There are about 5 species of deciduous, ground covering, rhizomatous, terrestrial ferns, in this genus. They occur in moist woodland throughout the Northern Hemisphere. Fronds, arising singly from long, creeping rhizomes in spring, are triangular and 2-pinnate or pinnatifid, with leaf blades that are bluish green, or yellow green and tilt at a right angles the light. Small, rounded sori on the undersides of the fronds, are without a protective indusia. Ideal groundcover or rock garden plant in moist, shady places.
Grow in preferably neutral to acidic, fertile, leafy, moist soil, enriched with compost before planting in light to deep shade. Can become invasive. Divide in spring.
G. robertianum – Limestone Polypod – This rhizomatous, deciduous, spreading fern from Eurasia and North America grows 14″ tall with an indefinite spread. It produces dull, dark green, broadly triangular, 2 or 3 pinnatifid fronds, to 14″ long, on stems to 6″ long. Pinnae are oblong to narrowly triangular, divided into oblong, smooth or finely toothed segments.
Zones 3-7
