Centaurea cyanus (cornflower, "Yagurumagiku")

Japanese name: ヤグルマギク （矢車菊）
Scientific name: Centaurea cyanus

[Overview]
An annual 30–100 cm tall.
The stems and leaves are covered with cottony hairs and look grayish.
The stem is erect and branches freely.
Leaves are alternate; on the lower part of the stem they are pinnately divided, and on the upper part they are linear-lanceolate, with entire or toothed margins.
Flower heads are solitary at the stem tips, about 4 cm across, and consist entirely of tubular florets, but the outer ones are enlarged and irregularly split at the tip.
The flower color is deep blue in the wild species, but there are garden cultivars in red, pink, white and other colors.
The fruit is an achene.

[Cultivation]
Propagate from seed.
It prefers a sunny, well-drained site.
It dislikes acidic soil and excessive moisture.
Take care not to let it become too wet; for potted plants, water thoroughly after the soil has dried, and for plants in the ground, rainfall is sufficient.
Too much fertilizer makes it leggy and prone to falling over, so if basal fertilizer is applied no further fertilizing is particularly necessary, but for potted plants, chemical fertilizer may be placed on the soil once a month.
Pests and diseases include damping-off and aphids.

[Notes]
The Japanese name likens the shape of the flower to a yaguruma (pinwheel).

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