Hypericum ×inodorum (tall tutsan)

Japanese name: ヒペリカム イノドルム
Scientific name: Hypericum ×inodorum

[Overview]
A deciduous or semi-evergreen shrub 0.6–2 m tall.
A hybrid between Kobozu-otogiri and Hypericum hircinum, with characteristics intermediate between the two.
It branches well from the base and grows densely.
The branches have ridges.
The leaves are simple and opposite, broadly ovate to elliptic-lanceolate and 3.5–11 cm long, and give off a fragrance when crushed.
The leaf base is rounded to heart-shaped and often clasps the stem; there is no petiole, or only a very short one.
The flowers are borne 1–23 per cyme at the branch tips; they are yellow, 5-petaled, about 1.5–3 cm across, and open star-shaped or cup-shaped.
The petals are oblanceolate to narrowly obovate, 0.8–1.5 cm long, clearly longer than the sepals at 1.5–2 times their length.
There are many stamens, divided into 5 bundles, 1.2–1.3 times the length of the petals and thus longer than the petals.
The sepals are elliptic-lanceolate to broadly ovate, 0.5–1 cm long, with blunt to rounded tips and entire margins.
The sepals are usually reflexed from the flowering period.
The fruit is a rounded, swollen capsule that ripens to coral pink to bright red.
The form and fruit color differ depending on the cultivar.
It closely resembles Kobozu-otogiri and is distinguished mainly by the petals being longer than the sepals and styles, the stamens being longer than the petals, and the sepals usually being reflexed in both the flowering and fruiting periods.

[Uses]
Branches in fruit are used as cut-flower material.

[Cultivation]
Propagate by cuttings or division.
It prefers sun to partial shade, good air circulation, and fertile, well-drained, moisture-retentive soil, and dislikes strong dryness.
Direct sunlight and dryness in summer can cause leaf scorch, so it is best to provide shade in summer.
If the site is too shady, it flowers poorly.
For potted plants, water thoroughly when the soil surface dries; for plants in the ground, water in the morning or evening during dry periods in summer, and otherwise rainfall is sufficient.
In spring and autumn, apply slow-release fertilizer placed on the soil.
If pruning, do it in winter.
Pests and diseases include thrips, aphids, scale insects, powdery mildew and rust.

[Notes]
There is confusion: a plant first distributed as a cultivar of Kobozu-otogiri was later reclassified as a cultivar of Hypericum inodorum.

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