Conoclinium coelestinum (blue mistflower)

Japanese name: コノクリニウム コエレスティヌム
Scientific name: Conoclinium coelestinum

[Overview]
A perennial up to about 90 cm tall, found in its native habitat at woodland edges, in moist grasslands, and along rivers and ponds.
The stem branches well.
The leaves are simple and opposite, ovate to elliptic.
The leaves on the upper part of the stem are triangular.
The leaf margins have coarse teeth.
Corymb-like or cyme-like inflorescences at the stem tips bear many small flower heads, blue to bluish purple or white.
The flower heads are about 7 mm across and consist only of tubular florets, with the styles protruding long beyond the flower.
The fruit is an achene.

[Cultivation]
Propagate by division or by stem cuttings.
It prefers a site in sun to partial shade with good drainage.
It spreads well by underground stems and is easy to grow.
For plants in the garden, watering is not necessary unless dry weather continues for a long time.
For potted plants, water thoroughly when the soil surface dries.
Too much fertilizer makes it grow too dense, so place a modest amount of slow-release chemical fertilizer on the soil twice, in spring and autumn.
There are almost no pests or diseases, but aphids may appear.

[Notes]
From its former genus name, it is also called Eupatorium.
Because the flowers resemble those of Ageratum, it is also sold under the name perennial Ageratum.

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