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Herbaceous Perennial

Cosmos atrosanguineus 'Black Magic'

chocolate cosmos 'Black Magic'

A tuberous perennial to 50cm producing a compact clump of deeply lobed, mid-green foliage. From mid-summer to mid-autumn upright stems carry individual, very dark red, chocolate-scented flowers which may be double, single or have quilled petals. This cultivar may be raised from seed

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Ultimate height

0.1–0.5 metres

Time to ultimate height

2–5 years

Ultimate spread

0.1–0.5 metres

Chalk

Loam

Sand

Moisture

Moist but well–drained

pH

Acid, Alkaline, Neutral

	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Full sun

Aspect

South–facing or West–facing

Exposure

Sheltered

Hardiness
Hardiness ratings
All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets
H1a: under glass all year (>15C)
H1b: can be grown outside in the summer (10 - 15)
H1c: can be grown outside in the summer (5 - 10)
H2: tolerant of low temperatures, but not surviving being frozen (1 to 5)
H3: hardy in coastal and relatively mild parts of the UK (-5 to 1)
H4: hardy through most of the UK (-10 to -5)
H5: hardy in most places throughout the UK even in severe winters (-15 to -10)
H6: hardy in all of UK and northern Europe (-20 to -15)
H7: hardy in the severest European continental climates (< -20)

Botanical details

Family: Asteraceae
Native to GB / Ireland: No
Foliage: Deciduous
Habit: Clump forming
Genus: Cosmos can be annuals or perennials with simple or pinnately divided leaves and large, long-stalked daisy-like flowers in summer
Name status: Accepted

How to grow

Cultivation

Grow in moderately fertile, moist but well-drained soil in full sun. Mulch in autumn; in cold areas lift tubers before first frosts and keep frost-free over winter

Propagation

See sowing seeds indoors

Suggested planting locations and garden types

City and courtyard gardens
Cottage and informal garden
Patio and container plants
Cut flowers
Flower borders and beds

Pruning

Deadhead to prolong flowering

Pests

Generally pest-free

Diseases

May be susceptible to foot rot and grey moulds

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