Aster ageratoides var. ageratoides f. ovalifolius ("Tamabashiroyomena")

Japanese name: タマバシロヨメナ （珠葉白嫁菜、玉葉白嫁菜）
Scientific name: Aster ageratoides var. ageratoides f. ovalifolius

[Overview]
A perennial 30–150 cm tall, found at forest edges in the mountains.
It has long creeping underground stems.
The stem branches in the upper part.
There are both basal leaves and stem leaves.
The stem leaves are simple and alternate, broadly ovate to ovate, 10–13 cm long and 5.5–6.5 cm wide.
The leaf margins have notched, tooth-like teeth.
There is a short petiole.
Flower heads are borne in corymbs at the top of the stem.
The flower heads are about 1.5–2 cm across, with white ray florets.
The involucre is 4 mm long, and the involucral bracts are in 3 rows.
The achene is narrowly obovate, 2.5 mm long, and the pappus is 4 mm long.

[Cultivation]
Propagate from seed, by division, or by stem cuttings.
It prefers a well-drained place in partial shade that does not receive the afternoon sun.
When planting in the ground, it is best to plant it under deciduous trees.
For potted plants, water thoroughly when the soil surface dries; for plants in the ground, rainfall is sufficient unless sunny weather continues in summer and the soil dries out.
If base fertilizer is applied, little further fertilizer is needed, but for potted plants a small amount of oil cake may be given in spring.
If you do not intend to collect seed, remove spent flowers promptly after flowering.
Pests and diseases include powdery mildew, slugs, cutworms and aphids.

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