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Aster (plant)

Aster is a common name used for several flowering plants in the daisy family (Asteraceae), especially showy, late-season perennials with star-like flower heads.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 26, 2026|2 min read| Fact-checked

Aster is a common name used for several flowering plants in the daisy family (Asteraceae), especially showy, late-season perennials with star-like flower heads. In modern classification, many plants once placed in the genus *Aster* have been reassigned to related genera, while the common name remains in use for a range of species. The plants are known for daisy-like blooms and for attracting pollinators in late summer and autumn.

Description

Asters are herbaceous flowering plants with daisy-like, star-shaped heads. Their blooms are usually purple, blue, pink, violet, or white, often with yellow or dark central disk florets.

Classification

Asters belong to the family Asteraceae. Modern taxonomy has narrowed the genus *Aster*, and many species once included there have been moved to other genera, especially in North America.

Ecology

Asters bloom late in the season and provide nectar and pollen when fewer plants are flowering. They are therefore valued by pollinators such as bees and butterflies.

Cultivation

Many asters are grown as ornamental perennials in gardens for their autumn colour. They are widely used in temperate landscapes and can vary greatly in height and growth habit by species.

Key facts

  • Aster is commonly used for a group of flowering plants in the daisy family, not just one species.
  • Asters typically bloom in late summer and fall, when many other garden plants are finishing flowering.
  • Their flower heads are composite, with ray florets around central disk florets.
  • Many asters are important nectar sources for butterflies, bees, and other pollinators.
  • Botanical classification has changed over time, and many North American species formerly placed in *Aster* are now in other genera such as *Symphyotrichum* and *Eurybia*.
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Canadian context

Asters are familiar to Canadian gardeners and wildflower enthusiasts, and several native North American species occur in Canada. Canadian sources also note their value in autumn landscapes and for pollinators.

Frequently asked questions

What is an aster?
Aster is a common name for daisy-family flowering plants known for star-like, late-season blooms.
Are all plants called asters in the same genus?
No. Many plants formerly placed in the genus *Aster* have been moved to related genera, though the common name is still widely used.
When do asters bloom?
Most asters bloom from late summer into late fall.
Why are they called asters?
The name comes from the Greek word for “star,” referring to the shape of the flower head.
What colours do aster flowers have?
Common colours include blue, purple, pink, violet, and white.

References

  1. Encyclopaedia Britannicahttps://www.britannica.com/plant/aster-plant
    Supports: Defines aster as a common term for fall-blooming leafy-stemmed herbaceous plants in the Asteraceae family.
  2. Canadian Wildlife Federationhttps://prod.cwf-fcf.org/en/resources/encyclopedias/flora/aster.html
    Supports: Describes asters as late-summer to late-fall bloomers with composite flower heads and pollinator value.
  3. Chicago Botanic Gardenhttps://www.chicagobotanic.org/plant-information/plant-profiles/aster
    Supports: Explains the Greek etymology, daisy-family placement, flower shape, colours, and pollinator attraction.
  4. North Carolina Extension Gardener Plant Toolboxhttps://plants.ces.ncsu.edu/plants/aster/
    Supports: Notes modern reclassification of the genus, North American species moving to other genera, and general growth and flowering traits.
  5. University of Wisconsin Horticulturehttps://hort.extension.wisc.edu/articles/asters/
    Supports: States asters are perennial Asteraceae plants that bloom late in the year in daisy-like colours and vary in size.