Centranthus macrosiphon (long-spurred valerian, "Usubenikanokoso")

Japanese name: ウスベニカノコソウ （薄紅鹿子草）
Scientific name: Centranthus macrosiphon

[Overview]
A biennial about 10–50 cm tall.
It germinates in autumn, overwinters, and flowers in early summer.
The stems and leaves are hairless, and the stem branches well from the base.
The leaves are simple and opposite, broadly ovate, about 4–7 cm long.
The leaf margins have notched teeth.
Petioles are present only on the leaves in the lower part of the stem.
Conical corymbs emerge at the top of the stem and bear many flowers.
The flowers are tubular, 10–13 mm across, with a 5-lobed tip, and pale pink, though some are white.
The corolla tube is long, and the pistil protrudes out of the flower.
The seeds have a pappus.

[History]
Cultivated plants have become naturalized and are seen in stone walls and cracks in asphalt.

[Cultivation]
Propagate from seed.
It also spreads well by self-sown seed.
It prefers slightly alkaline soil with good sun, drainage and ventilation.
It prefers a dry environment.
It tolerates partial shade, but flowering becomes poor.
It can overwinter outdoors in the Kanto region and south.
For potted plants, water thoroughly when the soil surface dries; for plants in the ground, rainfall is sufficient.
Keep it on the dry side in winter.
Fertilizer is not particularly necessary.
There are no particular pests or diseases.

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