Agapanthus campanulatus 'Cobalt Blue'

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African lily 'Cobalt Blue'

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Synonyms

Agapanthus campanulatus 'Chatto's Blue'

Herbaceous Perennial
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A compact clump-forming, deciduous, herbaceous perennial, producing narrow, strap-shaped, mid-green foliage, to a height of around 30cm (12in) and spreading to around 40cm (16in). Hemisperical heads of mid-blue, funnel-shaped flowers, on straight, green stems, to 60cm (24in) high, are produced in late summer.

Position

Full sun

Soil Types

Chalk, Loam, Sand

Max Height

0.5-1 metres

Max Spread

0.1-0.5 metres

Size

Time to Maturity
2–5 years
Max Spread
0.1-0.5 metres
Max Height
0.5-1 metres

Growing Conditions

Chalk Loam Sand
Moisture
Well–drained
pH
Acid or Alkaline or Neutral

Position

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)
H4

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Amaryllidaceae
Native to GB/Ireland
No
Foliage
Deciduous
Habit
Clump forming
Potentially harmful
Al parts of the plant are harmful if eaten
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 a light, well-drained soil and a position in full sun for best flowering. Plants benefit from regular watering and feeding during the growing season April to September. Protect plants in cold areas against frost damage by wrapping with several layers of fleece. See agapanthus cultivation for more details

Propagation

Propagate by division in spring, or by seed, but bear in mind that seed-raised plants may not come true to the parent plant, where it is a hybrid cultivar

Suggested planting locations and garden types

  • City and courtyard gardens
  • Cottage and informal garden
  • Mediterranean climate plants
  • Gravel garden
  • Coastal
  • Patio and container plants
  • Banks and slopes
  • Cut flowers
  • Flower borders and beds
  • Wall side borders

Pruning

No pruning required other than to remove any dead foliage or spent flower heads

Pests

May be susceptible to slugs and snails and agapanthus gall midge

Diseases

May be susceptible to a virus