Hosta 'Blue Mammoth' (_sieboldiana_)

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plantain lily 'Blue Mammoth'

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Synonyms

Hosta 'Blue Mammoth'

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Herbaceous Perennial
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A large, clump-forming deciduous perennial to 1m high, with thick, broadly heart-shaped, pale blue-green leaves. Produces clusters of white and pale purple flowers held on stems above the foliage in summer

Position

Full shade, Partial shade

Soil Types

Chalk, Clay, Loam, Sand

Max Height

0.5-1 metres

Max Spread

1-1.5 metres

Size

Time to Maturity
2–5 years
Max Spread
1-1.5 metres
Max Height
0.5-1 metres

Growing Conditions

Chalk Clay Loam Sand
Moisture
Moist but well–drained
pH
Acid or Alkaline or Neutral

Position

Full shade Partial shade
Aspect
East–facing or North–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)
H7

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Asparagaceae
Native to GB/Ireland
No
Foliage
Deciduous
Habit
Clump forming
Genus
Hosta are clump-forming herbaceous perennials with simple, ovate or lance-shaped leaves, often attractively coloured or variegated, and erect racemes of nodding, funnel or bell-shaped flowers in early summer
Name Status
Accepted

How to Grow

Cultivation

Grow in a shady spot in fertile soil that does not dry out, with shelter from cold, drying winds. Mulch annually in spring. Hostas in the ground may need watering during dry spells. See hosta cultivation for more detailed advice

Propagation

Propagate by division in early spring or late summer

Suggested planting locations and garden types

  • City and courtyard gardens
  • Cottage and informal garden
  • Flower borders and beds

Pruning

No pruning required

Pests

May be susceptible to slugs and snails

Diseases

May be susceptible to virus diseases