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Herbaceous Perennial

Agapanthus 'Big Ben'

African lily 'Big Ben'

A clump forming, evergreen herbaceous perennial that has broad strap-shaped leaves and very sturdy stems that hold large umbels of dark blue, trumpet-shaped flowers in summer

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Ultimate height

1–1.5 metres

Time to ultimate height

2–5 years

Ultimate spread

0.5–1 metres

Chalk

Loam

Sand

Moisture

Moist but well–drained, 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: Amaryllidaceae
Native to the UK: No
Foliage: Evergreen
Habit: Clump forming
Potentially harmful: Humans/Pets (dogs, cats): harmful if eaten. Wear gloves and other protective equipment when handling. For further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
Genus: Agapanthus are clump-forming perennials with narrowly strap-shaped leaves, evergreen in some species, and erect stems bearing umbels of funnel-shaped blue or white flowers
Name status: Accepted

How to grow

Cultivation

Grow in fertile moist but well drained soil in full sun. In cold areas mulch hardy hybrids in winter. In containers grow in a loam based compost (JINo.3). Apply a balanced liquid feed monthly from spring until flowering. For more information see agapanthus cultivation. May need winter protection

Propagation

Propagate by seed when ripe in autumn or spring and keep seedlings in cold frame overwinter - they will flower in 2-3years or Propagate by division every three to four years in spring

Suggested planting locations and garden types

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

Pruning

In late autumn remove or tidy up any remaining leaves, but seedheads can be left as they look attractive over winter

Pests

May be susceptible to slugs and snails and agapanthus gall midge

Diseases

May be susceptible to a virus

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