from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun Any of various tropical American plants of the genus Ageratum in the composite family, especially A. houstonianum, cultivated for their fluffy blue, purple, pink, or white flower heads.
  • noun Any of several other plants having flower clusters similar to those of ageratum.

from The Century Dictionary.

  • noun A genus of plants, natural order Compositæ, all American and chiefly tropical, nearly allied to Eupatorium.

from the GNU version of the Collaborative International Dictionary of English.

  • proper noun (Bot.) A genus of plants, one species of which (Ageratum Mexicanum) has lavender-blue flowers in dense clusters.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun uncountable Any of the genus Ageratum of tropical American herbs, annuals and perennials, from the sunflower family Asteraceae, tribe Eupatorieae; they are sometimes used in floral displays.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun rhizomatous plant of central and southeastern United States and West Indies having large showy heads of clear blue flowers; sometimes placed in genus Eupatorium
  • noun any plant of the genus Ageratum having opposite leaves and small heads of blue or white flowers


from The American Heritage® Dictionary of the English Language, 4th Edition

[New Latin Agēratum, genus name, from Greek agēraton, a plant (perhaps a type of rosemary), neuter of agēratos, ageless : a-, without; see a– + gēras, old age; see gerə- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From the genus name.


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  • Some seeds, such as ageratum, alyssum, impatiens, petunias, and snapdragons, should not be covered at all because they need light in order to germinate.

    unknown title 2009

  • A Fight for Flower Power Andy McMillan for The Wall Street Journal Dahlinova Dahlias at Metrolina Greenhouses in Huntersville, N.C. More photos and interactive graphics This year, Home Depot is touting an exclusive "Stellar Blue" ageratum, or floss flower, that hides faded blooms as it grows, requiring less clipping.

    The Garden Gloves Come Off Miguel Bustillo 2011

  • Spotted sipping on the wild ageratum, Conoclinium coelestinum, is our first image of a monarch butterfly this season.

    Whoa Nellie!* « Fairegarden 2009

  • She is surrounded by the native wild ageratum, Conoclinium coelestinum inherited with the property and planted with bronze carex self sown seedlings.

    First Frost Of Fall « Fairegarden 2009

  • We started snapping as the butterfly enjoyed the nectar from the wild ageratum, the name of which has changed so many times that the common name will suit our purposes here.

    Lucky Day « Fairegarden 2008

  • Do you have the wild ageratum, used to be a eupatorium of some sort?

    August Clues « Fairegarden 2008

  • We did best with ageratum and alyssum, impressing neighbors who said nobody had gardened that yard in human memory.

    Furniture 2008

  • Along the walks ageratum was planted in the following manner to serve as

    The Library of Work and Play: Gardening and Farming. Ellen Eddy Shaw

  • Often one sees a border of ageratum about such a one.

    The Library of Work and Play: Gardening and Farming. Ellen Eddy Shaw

  • This was money enough to buy seeds of ageratum, zinnia, dwarf nasturtium,

    The Library of Work and Play: Gardening and Farming. Ellen Eddy Shaw


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