Perennial

Japanese aster

Aster ageratoides

Japanese aster (Aster ageratoides) is a perennial. Light: full sun, part shade. Hardy down to -23 °C. Drought tolerance: medium. Non-toxic to children. Sold in local shops from about PLN 18.

Illustration of Japanese aster
An illustration of the typical shape of the mature plant, not a photo.

What it's good for, and what it isn't

A very tough, late-flowering aster: from late summer until the frosts it is covered in a haze of pale lilac, white or pinkish flowers, in sun or part shade and even in the drier ground at the foot of trees and shrubs. Its creeping rhizomes knit into a dense, weed-suppressing patch within a few years, so plant it among strong partners (shrubs, grasses, tall perennials) and chop back the edges with a spade in spring. It needs no staking, the stems stay upright.

Watch out for
In good soil the rhizomes run quickly and crowd out weaker perennials. Powdery mildew can appear in persistently hot, dry spots, although it is far more resistant than Michaelmas daisies. Slugs and snails may chew the young shoots.

Key facts

Light
Full sun, Part shade
Water need
Medium
Care
Low
Size after 10 years
70 cm × 60 cm
Hardiness
down to -23 °C
Foliage
Deciduous
Flowering
August–November, purple, white, pink

All details

Group Perennial
Light Full sun, Part shade
Size after 10 years 70 cm × 60 cm
Ultimate size 0.4–1 m × 30–60 cm
Hardiness down to -23 °C (USDA 6, RHS H7)
Soil Average garden soil, Clay, Sandy, Calcareous
Foliage Deciduous
Flowering August–November, purple, white, pink
Water need Medium
Drought tolerance Medium
Maintenance Low
Root aggressiveness Low
Suckering no data
Spreading High
Distance from buildings no data
Distance from paving no data
Litter not typical
Planting distance 40 cm
For dogs Non-toxic (uncertain)
For cats Non-toxic (uncertain)
For children Non-toxic
Typical price from about PLN 18

Toxicity data is for information only. If your pet or child has eaten a plant, contact a vet or a doctor.

Sizes and prices available

The same plant is sold as a small pot and as a specimen several metres tall, and the price follows. Prices are rounded and for guidance only.

Size
Typical price
size not stated approx. PLN 18

Frequently asked questions

Data updated: October 17, 2026 · How our data is made

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