Oenothera fruticosa (narrowleaf evening primrose, "Kidachimatsuyoigusa")

Japanese name: キダチマツヨイグサ （木立待宵草）
Scientific name: Oenothera fruticosa

[Overview]
A perennial 20–90 cm tall.
The stem is reddish, erect and branched.
The leaves include basal leaves and leaves arranged alternately on the stem; they are oblanceolate to ovate, with low tooth-like serrations on the margins.
The leaves on the stem are about 2.5–11 cm long.
The flowers are borne in racemes at the stem tips and are yellow, four-petaled, about 2.5–5 cm across.
The flowers open during the day.
The fruit is a club-shaped, ridged capsule.

[Cultivation]
Propagate from seed, by division, or by stem-tip cuttings.
It dislikes being transplanted, so sow directly where it is to be planted, or sow in pots and transplant while the seedlings are young.
It prefers sunny, well-drained soil.
For potted plants, water thoroughly when the soil surface dries; for plants in the ground, rainfall is sufficient unless summer brings a long spell of sunny weather and the soil becomes severely dry.
Too much fertilizer produces only leaves, so apply it sparingly; for potted plants, in addition to base fertilizer, place a small amount of slow-release fertilizer on the soil in spring.
For plants in the ground, no fertilizer is particularly necessary.
There are no particular pests or diseases.

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