Arisaema sikokianum (Japanese Jack-in-the-Pulpit, "Yukimochiso")

Japanese name: ユキモチソウ （雪餅草）
Scientific name: Arisaema sikokianum

[Overview]
A perennial found in mountain forests.
It has a flattened-globose corm underground, and the corm bears many small cormlets.
There are 2 leaves, each with 3–5 leaflets arranged like a bird's foot.
The leaflets are rhombic-elliptic with a pointed tip, and are entire or toothed.
The flower stalk is erect, taller than the leaf stalk, and bears a spadix at its tip.
The appendage at the tip of the inflorescence is pure white, club-shaped with a rounded, swollen end, and erect.
The spadix is enclosed in a spathe.
The spathe is purplish brown, with a thick, spongy tube and a white interior.
The limb of the spathe is 7–12 cm long, a triangular obovate shape with a tail-like tip, and is almost erect.
The fruit is an ovoid berry that ripens red.
The plant is dioecious; young plants are male and change to female as they grow.

[Uses]
Although poisonous, the corm is used medicinally.

[Cultivation]
Propagate from seed or by dividing cormlets.
When sowing seed, wash fully ripe fruit to remove the pulp and sow immediately.
It prefers shady, moist places.
Strong sunlight damages the leaves.
It dislikes dryness, so take care not to let it run short of water during the growing season, but too much moisture also causes root rot.
Do not let the soil dry out completely even during dormancy.
It likes fertilizer, so give liquid fertilizer once every 2 weeks during the growing season.
Pests and diseases include soft rot, southern blight, scale insects, aphids and slugs.

[Notes]
The Japanese name compares the appendage of the inflorescence to a rice cake (mochi).

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