Petrea volubilis (queen's wreath)

Japanese name: ペトレア ウォルビリス
Scientific name: Petrea volubilis

[Overview]
An evergreen climbing woody plant or semi-climbing shrub.
It grows quickly and in its native range climbs to 7.5–12 m, but in cultivation it is often about 4 m.
The base of the trunk sometimes reaches 10 cm in diameter.
Young stems, inflorescences and flower stalks have soft hairs.
The leaves are simple and opposite, elliptic to oblong, 5–20 cm long and 3–8 cm wide, with a rough upper surface.
The leaf margins are entire.
The petioles are 0.2–1 cm long.
If the temperature is high enough, it flowers all year round.
Racemes 8–30 cm long, erect or drooping, emerge from the branch tips or leaf axils and bear 15–30 flowers.
The flowers are funnel-shaped, deep purple to blue-purple, and 5-lobed; there are 5 slender, petal-like calyx lobes in a paler color than the flower, conspicuous like a shuttlecock.
The calyx remains after the flowers fall.
The fruit is berry-like and enclosed in the calyx, which acts like a wing or a float and helps with seed dispersal.

[Uses]
In its native range it is traditionally used medicinally.

[Cultivation]
Propagate by cuttings.
To overwinter, keep it at 10°C or higher, though it tolerates light frost.
It prefers a sunny, well-drained, fertile soil.
It tolerates shade, but flowering is poor if sunlight is insufficient.
For potted plants, water thoroughly from spring to autumn when the soil surface dries, and keep on the dry side in winter.
For established plants in the ground, rainfall is sufficient.
From spring to autumn, apply slow-release fertilizer placed on the soil.
Pests and diseases include scale insects and aphids.

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