Adiantum raddianum (Delta maidenhair fern, "Kobahoraishida")

Japanese name: コバホウライシダ （小葉蓬莱羊歯）
Scientific name: Adiantum raddianum

[Overview]
An evergreen terrestrial fern.
The rhizome creeps horizontally.
The leaves are triangular to ovate, 15–30 cm long and about 15 cm wide, 2–4 times pinnately compound, delicate and soft, and arch downward.
The leaflets are fan-shaped and wedge-shaped, and the tips of the veins reach notches in the leaf margin.
The sporangia are borne on the underside of the notched parts of the leaf margin; part of the leaf margin folds back to form a round kidney-shaped indusium-like cover that encloses the sporangia.
The petiole is slender, blackish purple-brown and glossy.

[Cultivation]
Propagate by division.
It tolerates temperatures down to about 5 °C, so bring it indoors for the winter and place it where dry warm air from heaters does not blow directly on it.
It prefers fertile, well-drained soil in bright shade.
Avoid strong wind, as it damages the leaves and petioles.
Take care not to let it dry out; from spring to autumn water so that the soil is always moist, and in winter water after the soil surface has dried.
It prefers an environment with high air humidity, so misting the leaves with a sprayer is beneficial.
From spring to autumn, apply slow-release chemical fertilizer or liquid fertilizer as appropriate.
Pests and diseases include slugs and scale insects.

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