Floss Flower
Photo courtesy of Flower Council of Holland


A summer delight for the floral artist.

by Steven W. Brown, AIFD

1 a brush-off. Ageratum houstonianum (pronounced a-ge-RAY-tum hew-stone-ee-AH-num) is most commonly known as floss flower or pussy-foot but is sometimes called “artist paintbrush” because of the brushlike appearance of its small blossoms, which grow in clusters. The leaves are “felted,” or hairy, and they are somewhat heart-shaped, with shallowly toothed or serrated edges.

2 the name game. The name Ageratum comes from the Greek roots “a” (without) and “geras” (age), referring to the flowers’ retaining their color for a long time. The species houstonianum was named after William Houston (1695-1733), an American physician who collected plants in the Antilles and Mexico.

3 family lines. Ageratum is a member of the Compositae or Asteraceae family, which has the largest number of commercially grown plants in the world. Relatives include Dahlias, Asters, cornflowers, daisies, sunflowers and chrysanthemums as well as many vegetable crops like lettuce. Ageratums are indigenous to the Central American countries of Mexico, Belize, Guatemala and Honduras as well as the West Indies and Southern Florida.

4 a beautiful season. Ageratums contribute blue-violet, red-violet, violet-blue, lilac, pink and white to the floral artist’s palette. They are most available from June through October from both domestic and Dutch growers although some varieties are available year-round from Holland.

5 exam time. When shopping for Ageratums, look for full buds that are showing color and are about one-third open. Make sure the centers are tight. If they are harvested too early, it will be difficult to open the blossoms. Avoid bunches that have signs of mold or damaged foliage and flowers.

6 proper care. Upon arrival in your shop, unpack the bunches and remove any foliage that would fall below the water line in vases or buckets. Cut the stems on an angle, and dip or place them into a hydration solution. Next place the stems into a clean bucket containing a properly prepared cut flower food solution that is several inches deep.

7 cold storage is OK. Keep Ageratums in a brightly lit, warm area where they can open and develop for at least two hours. These flowers can be cooled and stored in a floral refrigerator at 34 F to 38 F. They also will do well in room-temperature conditions.

8 time is on your side. With good care, Ageratums will last an average of seven to 12 days. Some varieties will dry well and can be used in permanent and dried arrangements.

9 freshen the water. When designing with Ageratums in floral foam, saturate the foam in a fresh flower food solution to ensure proper hydration for the thirsty flowers. Provide customers with extra flower food packets, and advise them to change the water in their arrangements regularly. Caution them also to display arrangements away from heat sources and direct sunlight to maximize vase life.

10 the doctor is in. Ageratums are utilized in traditional medicine by various cultures worldwide. Extracts are used to treat pneumonia and to cure wounds and burns. Ageratums also are used to kill bacteria, to prevent dysentery and to prevent the formation of gall or kidney stones.

Steven W. Brown, AIFD, is a professor and department chair of horticulture and floristry at City College of San Francisco with 27 years of consulting and educational experience in the floral industry. Contact him at or (415) 239-3140.

Some information provided by the California Cut Flower Commission and Repetto Nursery, Half Moon Bay, Calif.