Hypericum perforatum subsp. chinense ("Kogomebaotogiri")

Japanese name: コゴメバオトギリ （小米葉弟切）
Scientific name: Hypericum perforatum subsp. chinense

[Overview]
A perennial up to about 80 cm tall, found along roadsides and similar places.
It spreads by underground stems and forms colonies.
The stem is erect, has two ridges, and branches freely.
Leaves are simple and opposite, elliptic-lanceolate to broadly linear, 1–1.5 cm long, with translucent glandular dots and black glandular dots along the leaf margin.
Cymes at the branch tips bear many flowers.
The flowers are yellow with 5 petals, about 2 cm across, with many yellow stamens.
The petal edges have black dots.
The fruit is a capsule.

[History]
It was discovered in Mie in the 1930s and is now naturalized in many places.

[Uses]
It is used medicinally.

[Cultivation]
Propagate from seed, by cuttings, or by division.
It prefers a sunny site with good drainage and good water retention, and dislikes dryness.
Direct summer sun and dryness can cause leaf scorch, so it may also be grown in partial shade.
It spreads by underground stems, so to keep it from multiplying too much, make a frame underground or plant it in a large pot and bury the pot.
For potted plants, water thoroughly when the soil surface dries; for plants in the ground, rainfall is sufficient unless summer brings a long sunny spell and severe dryness.
Do not let it dry out during the flowering season.
Fertilizer is hardly necessary, but if applied, give a small amount after flowering.
If pruning, do it in winter.
There are no particular pests or diseases.

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