Ageratum – Ageratum houstonianum

Common Name: Flossflower, Ageratum

Botanical Name: Ageratum houstonianum, a-ge-RAY-tum hew-ston-ee-AH-tum

Decorative Life: 7-10 days.

Flower Color: Blue, Pink, White

Availability: Fall, Summer

Plants perform better in the landscape if grown in mixes containing both a wetting agent and hydrogel. Plugs can be stored for up to six weeks in the dark at 45F but do much better if provided as little as 5 ft-c of light during storage. Deeper and larger volume growing containers can improve shelf life.

Can be held at 34-38F.

• The Compositae or aster family is vast, with over 20,000 species, and is also one of the most developed families. It was named Compositae because the flowers are actually a “composite” of many individual flowers into one head. Hence, when children pull one “petal” off at a time, saying “she/he loves me, loves me not”, they are actually removing a complete flower, not just a petal.
• Ageratum, Greek (a-, without, and geras, age) for not growing old probably in reference to the flowers retaining their color for a long time.
• Named after William Houston, American physician who collected plants in the Antilles and Mexico, died in 1733.
• Insects and diseases are often problems during production. Some favorite cultivars and their respective flower colors include ‘Hawaii Blue’ and Hawaii Royal (blue/violet). Full sunlight would be best.

Using ‘Blue Puffs’, Latimer and Oetting (1999) showed that low nitrogen fertilzation reduced aphid infestation levels while ebb and flow irrigation reduced mite populations compared to overhead watering.