Kalmia latifolia (mountain laurel)

Japanese name: カルミア
Scientific name: Kalmia latifolia

[Overview]
In its native habitat, an evergreen shrub or small tree 3–9 m tall.
It branches well.
The leaves are simple and alternate, oblong to elliptic-lanceolate, 3–12 cm long and 1–5 cm wide, and thick.
The leaf margins are entire.
The petioles are 1–3 cm long.
Panicles at the branch tips bear 20–40 white to pink flowers 1.5–2.5 cm across.
The buds are shaped like konpeito (star-shaped sugar candy) and are dark in color.
When open, the flower is saucer-shaped with a pentagonal outline, and has pockets that hold the anthers of the stamens.
There are 10 stamens, which spring out and scatter pollen when stimulated by insects or the like.
The fruit is a capsule.

[Uses]
The wood is useful, and the roots are also used as a substitute material for briar pipes.
The leaves are poisonous but are used medicinally.

[Cultivation]
Propagate from seed or by layering.
Cuttings and grafting are also possible, although the rooting rate is poor.
It prefers fertile, acidic soil with good drainage and ventilation.
Avoid dry sites, or prevent the base of the plant from drying out by mulching or similar means.
From spring to autumn, it is best placed where it gets half a day of sun without the western sun or direct summer sunlight; from autumn to spring, place it in a sunny spot protected from cold wind. In the ground, a place in the shade of deciduous trees is good.
For potted plants, from autumn to spring water thoroughly when the soil surface dries; in midsummer, water twice a day, in the cool morning and evening, so that the water also reaches the leaves.
For plants in the ground, rainfall is sufficient except in summer; in summer, water in the cool morning or evening so that the water also reaches the leaves, and in winter, if dry weather continues, water in the morning on a warm day.
Fertilize three times in total: fertilizer in winter, fertilizer after flowering, and in autumn, applying organic fertilizer or a slow-release chemical fertilizer with equal amounts of the three components around the plant.
Do not prune; instead, adjust the shape of the tree by removing excess buds in spring to early summer.
Remove spent flowers promptly.
Pests and diseases include brown spot, Ciborinia flower blight, pestalotia disease, aphids, scale insects, leafrollers and lace bugs.

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