Ilex crenata 'Convexa' (f)

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Japanese holly 'Convexa'

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Japanese holly 'Convexa' Dorling Kindersley 2003
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Shrubs
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A broad, dense, bushy evergreen shrub about 1m tall, with small glossy, yellowish-green, convex (curved) leaves to 2cm long. Flowers small and white, followed by abundant glossy black berries if pollinated by a male Japanese holly

Position

Full sun, Partial shade

Soil Types

Loam, Sand

Max Height

0.5-1 metres

Max Spread

1-1.5 metres

Size

Time to Maturity
5–10 years
Max Spread
1-1.5 metres
Max Height
0.5-1 metres

Growing Conditions

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

Position

Full sun Partial shade
Aspect
West–facing or East–facing or South–facing
Exposure
Exposed or 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)
H6

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Aquifoliaceae
Native to GB/Ireland
No
Foliage
Evergreen
Habit
Bushy
Potentially harmful
Fruit are ornamental - not to be eaten. Wear gloves and other protective equipment when handling. Pets: Fruit are ornamental - not to be eaten - see the HTA guide to potentially harmful plants for further information and useful contact numbers
Genus
Ilex can be deciduous or evergreen shrubs and trees with often spiny leaves, small white flowers (male and female usually on separate plants) and, on female plants, showy berries in autumn
Name Status
Accepted

How to Grow

Cultivation

Grow in slightly acidic soil in a location which enjoys cooler, damp summers. Avoid waterlogged and very dry soils. Does not perform well as hedging in most parts of the UK. For alternatives to this and Box hedging, please go to Box alternatives and How to choose Box alternatives. Although partial shade is suitable, there is better golden leaf colour in full sun

Propagation

Propagate by semi-ripe cuttings in late summer or early autumn or propagate by hardwood cuttings in January with bottom heat

Suggested planting locations and garden types

  • Patio and container plants
  • Architectural
  • City and courtyard gardens
  • Coastal
  • Cottage and informal garden
  • Wildlife gardens
  • Low Maintenance
  • Flower borders and beds
  • Garden edging

Pruning

Pruning group 1; trim hedges in early spring

Pests

May be susceptible to scale insects, holly leaf miner and young shoots may be susceptible to aphids

Diseases

May be susceptible to holly leaf blight, Phytophthora root rot and sometimes honey fungus