Triantha japonica ("Iwashobu")

Japanese name: イワショウブ （岩菖蒲）
Scientific name: Triantha japonica

[Overview]
A perennial 20–50 cm tall, growing in subalpine wetlands mainly on the Sea of Japan side.
The rhizome is short, grows obliquely, and has brown fibers attached.
The leaves consist of basal leaves and leaves on the flower stalk; the basal leaves are linear, 5–40 cm long and 0.2–0.8 cm wide.
The flower stalk, 20–50 cm tall, bears 1–2 small linear alternate leaves.
A compound raceme at the tip of the flower stalk bears flowers in threes at the same node, and the nodes have bracts.
The flowers are about 1–1.5 cm across, white to very pale pink with 6 petals, and the buds are reddish purple.
There are 6 stamens, and the black anthers are conspicuous.
Because the side branches of the compound raceme are reduced, it looks like a simple raceme.
The upper part of the flower stalk, the inflorescence and the flower stalks have glandular projections and are sticky.
The fruit is an obovate capsule 5 mm long that splits into 3 when ripe, and the seeds have a thread-like projection at one end.

[Cultivation]
Propagate from seed or by division.
It prefers partial shade and moderately moist, well-drained soil; it also grows in full sun, but strong direct sunlight in summer scorches the leaves.
Plant it in well-drained soil such as soil for mountain wildflowers, or sphagnum moss alone is also fine.
Water thoroughly when the surface of the planting medium dries.
In spring and autumn, apply slow-release fertilizer placed on the soil.
There are no particular pests or diseases.

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