Chrysanthemum

Chrysanthemum coronarium L.

Order: Asterales

Family: Asteraceae

Names:

Chrysanthemum is from the Greek chrysos meaning gold and anthemom meaning flower and refers to the yellow flowers.
Coronarium
Chrysanthemum

Other Names:

Crown Daisy
Summer Chrysanthemum

Summary:

An annual plant with yellow ornamental flowers.

Description:

Cotyledons:

Two.

First leaves:

Leaves:

Stipules -
Petiole -
Blade - Deeply divided, smooth.
Stem leaves -

Stems:

Erect, up to 600 mm tall.

Flower head:

Flowers:

Yellow, large, 60 mm diameter, daisy type. Strongly scented.
Ovary -
Calyx -
Perianth -
Sepals -
Petals -
Stamens -
Anthers -

Fruit:

Seeds:

Roots:

Key Characters:

Biology:

Life cycle:

Annual. Buds initiate when day length is 13.5 hours and it takes 8-11 weeks from bud initiation to flowering. Year round production can be achieved where light and temperature are controlled. Natural crops flower just before mothers day in May.

Physiology:

Frost susceptible.
Temperatures below 160C or above 270C may cause abnormal bud development.

Reproduction:

Normally by cuttings.
Absolute short day plants requiring 13.5 hours day light for flower bud initiation and 14.5 hours for bud development. They won't form buds when the day length exceeds 14.5 hours. (It is actually the night length or length of darkness rather than the day length that controls reproduction).

Flowering times:

Spring in WA.

Seed Biology and Germination:

Vegetative Propagules:

Hybrids:

Allelopathy:

Population Dynamics and Dispersal:

Origin and History:

Mediterranean. China.

Distribution:

NSW, SA, WA.

Courtesy Australia's Virtual Herbarium.

Habitats:

Climate:

Temperate. Mediterranean.

Soil:

Well drained soils and irrigation are usually required.

Plant Associations:

Significance:

Beneficial:

Ornamental flower.
The natural insecticide pyrethrum is extracted from related species and gardeners use this plant to reduce insect problems.

Detrimental:

Weed of roadsides and disturbed areas.

Toxicity:

Not recorded as toxic.

Legislation:

None.

Management and Control:

Thresholds:

Eradication strategies:

Herbicide resistance:

Biological Control:

Pests include Green Peach Aphid, Helicoverpa, Leaf Roller and Spider Mite.
Diseases include Botrytis Petal Blight or Grey Mould, Fusarium Stem Rot and Wilt, Mycosphaerella Ray Blight, Powdery Mildew, Rust and a Leaf Nematode causing leaf blotch.

Related plants:

Corn Marigold (Chrysanthemum segetum)
Teneriffe Daisy (Chrysanthemum foeniculaceum)

Plants of similar appearance:

References:

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P879.

Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (1997). Western Weeds. A guide to the weeds of Western Australia. (Plant Protection Society of Western Australia, Perth, Western Australia). P92-93. Photo.

Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne). #308.1.

Reid, R.L. (1990) The Manual of Australian Agriculture. (Butterworths, Sydney). P209-210.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.