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Annual Biennial

Alcea rosea 'Blacknight' (Spotlight Series)

hollyhock 'Blacknight'

A short-lived perennial with lobed rounded leaves and long, erect pyramids of open funnel-shaped almost black single flowers with a contrasting pale yellow eye in summer.

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Size
Ultimate height
1.5–2.5 metres
Time to ultimate height
1 year
Ultimate spread
0.1–0.5 metres
Growing conditions
Chalk
Loam
Sand
Moisture
Well–drained
pH
Acid, Alkaline, Neutral
Colour & scent
StemFlowerFoliageFruit
Spring Green
Summer Black Green
Autumn Green
Winter
Position
  • Full sun
Aspect

South–facing

Exposure
Exposed or Sheltered
Hardiness
H5
Botanical details
Family
Malvaceae
Native to the UK
No
Foliage
Deciduous
Habit
Columnar upright
Genus

Alcea are robust biennials or short-lived perennials with showy funnel-shaped flowers borne in tall, erect racemes in summer

Name status

Accepted

How to grow

Cultivation

Thrives in well-drained, moderately fertile soil in full sun. May need support on exposed sites, see staking: perennials

Propagation

Propagate by seed

Suggested planting locations and garden types
  • Architectural
  • City and courtyard gardens
  • Cottage and informal garden
  • Low Maintenance
  • Wall side borders
Pruning

Cut back dead foliage after flowering, or pull out and discard - growing as annuals or biennials can help limit the spread of rust

Pests

May be susceptible to cutworms and slugs on young growth, and to capsid bugs, aphids and mallow flea beetles

Diseases

May be susceptible to hollyhock rust

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