Arisaema yamatense subsp. yamatense ("Murotennansho")

Japanese name: ムロウテンナンショウ （室生天南星）
Scientific name: Arisaema yamatense subsp. yamatense

[Overview]
A perennial found in mountain forests.
It has a flattened-globose corm underground.
The sheathing leaves and the lower parts of the leaf stalks form a pseudostem.
There are 2 leaves, each with 7–17 leaflets arranged like a bird's foot.
The leaflets are narrowly elliptic to linear with a sharply pointed tip, and are entire or finely toothed.
The leaf axis is well developed.
The lower leaf (second leaf) is attached so as to touch the upper leaf (first leaf), and is markedly small.
The flower stalk often emerges before the leaves open, stands erect, and bears a spadix at its tip.
The appendage at the tip of the inflorescence is green, with a slightly swollen tip that bends forward.
The spadix is enclosed in a spathe.
The spathe is pale green, sometimes tinged with purple, and the limb is a triangular broadly ovate shape with an abruptly sharp tip, often shorter than the tube.
The inside of the spathe is densely covered with papillae and feels rough.
The fruit is an ovoid berry that ripens red.
The plant is dioecious; young plants are male and change to female as they grow.

[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.

View this page in Japanese (日本語)