Primula reinii var. reinii ("Koiwazakura")

Japanese name: コイワザクラ （小岩桜）
Scientific name: Primula reinii var. reinii

[Overview]
A perennial 5–10 cm tall, found in rocky places.
It has a slender rhizome.
The leaves are simple and basal, round, 1.5–4 cm across, becoming 5–7 cm across at the fruiting stage; the margin is shallowly 7–9-lobed, and the lobes are further divided.
The leaf surface is much wrinkled, and both sides have soft hairs.
The petiole is 3–10 cm long.
At the tip of a flower stalk 5–10 cm tall, an umbel bears 1–5 reddish-purple flowers with a yellow eye.
The corolla is 1.8–2.5 cm across and 5-lobed, with each lobe further divided in two at the tip.
The fruit is an oblong capsule 7–12 mm long.

[Cultivation]
Propagate from seed or by division.
It prefers a cool, well-drained, airy environment.
From sprouting until flowering, give it full sun; in summer, place it in well-ventilated partial shade so that it is not weakened by heat and dryness.
Rain damages the flowers during flowering, so it is best to give it rain protection.
During the growing season, water thoroughly as soon as the soil surface begins to dry, and take care that it does not dry out even during dormancy.
Apply a slow-release fertilizer rich in phosphate and potash as a base fertilizer, and give diluted liquid fertilizer once every 2 weeks to 1 month during the flowering period, making sure no fertilizer remains in summer.
If you do not want to collect seed, cut off the flowers together with their stalks once they finish, so the plant does not become exhausted.
Pests and diseases include armyworms, slugs and nematodes.

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