Introduction

Dendranthema x grandiflora is a spreading perennial that reaches a height of about 6 inches (Figure 1). However, it may attain a height of 7 to 24 inches when in flower. Beautiful flower spikes appear in the fall and spring seasons. These flowers come in colors of brown, red, white, yellow, pink, or red-orange. The flowers may be cut for flower arrangements, and the plant is commonly massed in the landscape.

General Information

Scientific name: Dendranthema x grandiflora

Pronunciation: den-dran-THEEM-uh x gran-dif-FLOR-uh

Common name(s): garden mum, garden chrysanthemum, florists' chrysanthemum

Family: Compositae

Plant type: perennial; herbaceous

USDA hardiness zones: 8 through 10A (Figure 2)

Planting month for zone 7: Oct; Mar; Apr

Planting month for zone 8: Oct; Mar; Apr

Planting month for zone 9: not recommended

Planting month for zone 10 and 11: not recommended

Origin: not native to North America

Uses: mass planting; edging; attracts butterflies

Availability: generally available in many areas within its hardiness range

Description

Height: 1 to 2 feet

Spread: 1 to 2 feet

Plant habit: round

Plant density: dense

Growth rate: moderate

Texture: fine

Foliage

Leaf arrangement: alternate

Leaf type: simple

Leaf margin: lobed

Leaf shape: ovate

Leaf venation: pinnate

Leaf type and persistence: deciduous

Leaf blade length: 2 to 4 inches

Leaf color: green

Fall color: not applicable

Fall characteristic: not applicable

Flower

Flower color: pink; brown; red; white; yellow; red-orange

Flower characteristic: spring flowering; fall flowering

Fruit

Fruit shape: unknown

Fruit length: unknown

Fruit cover: unknown

Fruit color: unknown

Fruit characteristic: inconspicuous and not showy

Trunk and Branches

Trunk/bark/branches: typically multi-trunked or clumping stems

Current year stem/twig color: green

Current year stem/twig thickness: medium

Culture

Light requirement: plant grows in part shade/part sun

Soil tolerances: acidic; slightly alkaline; sand; loam; clay

Soil salt tolerances: unknown

Plant spacing: 18 to 24 inches

Other

Roots: not applicable

Winter interest: no special winter interest

Outstanding plant: plant has outstanding ornamental features and could be planted more

Invasive potential: not known to be invasive

Pest resistance: very sensitive to one or more pests or diseases which can affect plant health or aesthetics

Use and Management

Garden mums will prosper in full sun to partial shade and prefer well-drained soils amended with organic matter. In sandy soils, a 3 to 4 inch layer of peat or compost should be worked into the top six inches of the soil. From late spring through mid-August, lightly prune stems without flower buds whenever they grow over six inches by snipping off the top 2 inches of growth. Prune off dead flower spikes.

Some varieties of garden mum produce tall flower spikes which must be staked. Chrysanthemum pacificum, a plant grown for its attractive, variegated foliage makes an interesting ground cover in full sun locations in central and north Florida.

Propagate Dendranthema x grandiflora by division or cuttings.

Pests and Diseases

The garden mum is relatively pest tolerant and has few pests of major concern. Leaf blight is probably the biggest concern.