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Ageratum

Annual Flower

Also known as Flossflower
Ageratum houstonianum
Asteraceae Family
Synonym: A. mexicanum

One of the few annuals to tolerate light shade, the most commonly used varieties are dense, rounded border plants providing a touch of rare blue to the garden setting. They are so compact and floriferous that they are often used in formal designs that need a blue color. Some varieties are white or pink, and few are tall with a loose form. Its fringed, button-like flowers are very unique and provide interesting texture.

	Site and Plant Characteristics
	Growing Information
	Varieties

Site Characteristics

Sunlight:

full sun
part shade

Prefers warm weather. In very hot climates, prefers part shade.

Special locations:

outdoor containers
xeriscapes

Plant Traits

Lifecycle: annual

Ease-of-care: easy

Height: 0.5 to 2 feet

Spread: 0.5 to 1 feet

Bloom time:

mid-summer
late summer
early fall
mid-fall

Flower color:

blue
white
pink

Foliage color: medium green

Foliage texture: medium

Shape:

cushion, mound or clump
loose and formless

Shape in flower: same as above

The small (1/4-inch), tufted flowers are clustered in dense, rounded heads about 1 inch in diameter.

Special Considerations

Special characteristics:

deer resistant
non-aggressive
non-invasive
native to North America - Mexico

Attracts:

butterflies

Special uses:

cut flowers - Only the taller varieties, not the dwarf bedding varieties.

Growing Information

How to plant:

Propagate by seed - Start seeds indoors 6 to 8 weeks before last frost, do not cover seeds, as they need light to germinate.

Germination temperature: 70 F to 75 F

Days to emergence: 5 to 10

Maintenance and care:

Pinch back plants to keep rounded and bushy, deadhead to keep in flower.
More growing information: How to Grow Annuals

Pests:

Spider mites
Whitefly

Diseases:

Oedema
Parasitic nematodes
Powdery mildew
Root rot

Varieties

Various shades of pink and blue are available, as are dwarf plants which only grow to about 6 inches tall
�Southern Cross� is suited for containers in part shade.
�Hawaii� Series flowers in shades of blue, white or pink. Very popular series.
�Bavaria� has white flowers with bright turquoise borders. Grows to 1 foot tall.
�Red Top�has very striking vivid magenta flowers on 3-inch heads. 2 to 2.5 feet tall.
'Blue Danube' is a classic hybrid with purple-blue flowers in dense heads. Compact and reliable garden performer.
�Pinky Improved� has showy flowers that are dark pink in the centers, fading to pale pink at their fringed edges. Compact and showy.
�Southern Cross� has bicolor flowers are white in the center, gradually turning to cornflower blue near the edge. Compact and showy.