Common Name: Elkhorn fern.
Etymology: Platycerium: from the Greek word ‘platys’ meaning flat and ‘ceras’ meaning a horn (referring to leaf shape). bifurcatum: meaning fork in two branches (again refering to leaf shape).
Origin: South eastern Australia from NSW to Queensland, Lord Howe Island and Java, New Guinea.
Description: Large bracketing epiphytic fern that grows on trees and rocks in natural habitat.
Foliage: Two types: Sterile – Pale green becoming brown and papery with age. They are stalkless and spongy near the centre becoming thin and round towards the edges. They are roughly circular to kidney shape, 10-30cm diameter with lobed margins. These leaves form a nest that collects debris. Each year new leaves grow over old ones forming a rich, moist humus for roots to grow into, preventing plant from drying out. Fertile – These fronds are a darker green, leathery, semi erect to pendulous 25-100cm long (New leaves are hairy at the ends). They are narrow at the base and forking at the end in lobes up to 30cm long. Sporangia form brown patches on the bottom surface of the end segment of leaves. Small plants are formed on outer edges of the nest increasing the clump and allowing the plant to spread.
Growth Requirements: Prefers a humid, warm protected position with filtered light and plenty of debris from trees. Saying this, it is extremely hardy and will survive heat (picture below) and temperatures into the minuses (for a short time only as regular frosts will kill them). In colder winter conditions it is wise to keep these plants slightly dry. Fertilize sparingly with organic compost.
Uses: Rainforest gardens, Australian native gardens, vertical and small space gardens.
Propagation: The easiest way to propagate is by removing plantlet or plantlets from nest (using knife or spatula ensuring plant and roots are removed) and placing in new location. Can be also propagated from spore by placing spore producing leaf in paper bag, leaving it until a brown dust is formed in bottom of bag (spores). Spores can be spread evenly over sterile peat moss mix in a pot and pot placed in warm position with indirect sunlight keeping mix moist using wicking method.
Sources of Information:
- Australian Palms, Ferns, Cycads and Pandans by Leonard Cronin.
- Photography by Simon Schubert.