Click for previous Image Image 1 of 4 Conoclinium coelestinum Hardy Ageratum

Flowers are actually bluer than this pic shows... the blue is hard to capture through the lens.

Conoclinium coelestinum

Hardy Ageratum

Plant Type:


Conoclinium coelestinum (aka Eupatorium coelestinum) - Hardy Ageratum aka Blue Mist Flower flowers in October for us with large flattened domes of congested florets with congested filament-like petals that en masseare like little shag throw rugs. They occur atop stems cloaked in clean green rounded leaves. Flowers to the eye are blue; these pics appear more purple and haven't captured the definite shade of blue. This plant is wonderful in the autumn garden - just gorgeous with Leucoseptrum stellipilum 'October Moon' or Callicarpa dichotoma 'Duet'. Native from New York to Florida, west to Texas, north to Nebraska east to New York minus Iowa but add Michigan. Fertile draining soil. Half to full sun. In the north Blue Mist Flower will tolerate light frosts when in flower if planted in a south facing site. Established potted Blue Mist Flower, cutting grown.


24-36 in


36-48 in




(5a)5b to 10
What is my hardiness zone?

Characteristics and Attributes for Conoclinium coelestinum

Season of Interest (Flowering)

  • Late Summer / Autumn

Season of Interest (Foliage)

  • Spring / Summer / into Autumn

Nature Attraction

  • Butterflies
  • Honey Bees & Native Bees


  • Full Sun
  • Mostly Sunny


  • Border
  • Natural Garden
  • Drought Tolerant
  • Cutting Garden
  • Cottage Garden
  • Wildlife Garden

Growth Rate in the Garden

  • Moderately Fast


  • Draining
  • Fertile
  • Average


  • Central and Eastern U.S.

Propagated By

  • Cutting Grown