Cerastium tomentosum (snow-in-summer, "Shiromiminagusa")

Japanese name: シロミミナグサ （白耳菜草）
Scientific name: Cerastium tomentosum

[Overview]
An evergreen perennial 15–30 cm tall.
In its native habitat it grows on dry bare ground.
The whole plant is densely covered with hairs and tinged silvery gray.
It spreads by underground stems and grows in a mat.
Leaves are simple and opposite, linear to lanceolate, about 3 cm long.
There is no leaf stalk.
A dichasial cyme at the stem tip bears up to about 15 flowers.
The flowers are white and 5-petaled, 1.5–2.5 cm across, with petals shallowly divided in two.
There are 10 stamens.
The fruit is a capsule.

[Cultivation]
Propagate by division or by stem cuttings.
It prefers a sunny, well-drained, well-ventilated site with lean soil.
It dislikes heat and humidity, so in summer keep it in a cool place in partial shade, or in warm regions do not carry it through summer and treat it as an annual.
It is better kept on the dry side; for potted plants, water thoroughly after the soil has dried, and for plants in the ground, rainfall is sufficient.
If basal fertilizer is applied no more is particularly needed, but for potted plants a small amount of slow-release fertilizer may be placed on the soil in spring and autumn.
Cutting it back hard after flowering improves ventilation and makes it easier to get through the summer.
There are no particular pests or diseases.

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