Allamanda blanchetii (purple allamanda, "Murasakiariakekazura")

Japanese name: ムラサキアリアケカズラ （紫有明葛）
Scientific name: Allamanda blanchetii

[Overview]
In Japan it is treated as a climbing evergreen woody plant, but in hot, strongly sunlit environments it becomes shrubby.
It may also drop its leaves when temperatures fall.
Young branches grow long and slender, climbing up to about 3 m in height.
The young leaves and stems bear soft hairs.
The leaves are simple, in whorls of 4, ovate-elliptic and 7–12 cm long, with pointed tips and a somewhat glossy surface.
The leaf margins are entire.
It flowers all year round if the temperature is sufficient.
The flowers are borne at the branch tips and are reddish purple, which is rare in this group, with a darker throat; they are funnel-shaped, about 7.5 cm across, with 5 lobes at the tip, and the lobes are rounded and overlapping.
The fruit is a capsule covered with soft spines.
The seeds are flat with a wing around the edge.

[Cultivation]
Propagate mainly by cuttings, although seed and grafting are also possible.
For cuttings, wash off the white latex that comes out of the cut surface before inserting them.
It prefers fertile soil with good sun and drainage.
In warm regions it is hardy, grows well regardless of soil type, and is often used for greening in Okinawa.
It needs about 15 degrees to overwinter, so outside Okinawa, grow it in a pot and bring it indoors to a sunny spot in winter.
For potted plants, water thoroughly when the soil surface dries; for plants in the ground, rainfall is sufficient unless sunny weather continues in summer and the soil dries out.
Apply slow-release chemical fertilizer on the soil from spring to autumn.
It sprouts vigorously and grows densely, so prune as appropriate.
Pests and diseases include sooty mold, damping-off and aphids.

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