• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Magnolia grandiflora

bull bay

  • Other common names bull bay
    bullbay

    great laurel-leaved magnolia
    large-flowered magnolia
    laurel magnolia
    loblolly magnolia
    southern magnolia

    see more
  • Family Magnoliaceae

  • Genus Magnolia can be deciduous or evergreen trees or shrubs, with large, showy, often fragrant flowers, often opening before the leaves, and sometimes followed by colourful cone-like fruit

  • Details M. grandiflora is a large, rounded evergreen shrub or tree with glossy dark green, leathery, oblong-elliptic leaves, often rusty-brown beneath, and highly fragrant, cup-shaped, cream flowers to 25cm across in late summer and autumn

  • Plant range SE USA

Characteristics

  • Foliage Evergreen

  • Habit Bushy

  • Fragrance Flower

  • 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)

    H5

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect East-facing or South-facing or West-facing

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Clay

    Clay

  • Sand

    Sand

  • Chalk

    Chalk

  • MoistureWell-drained, Moist but well-drained

  • SoilLoam, Clay, Sand, Chalk

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height Higher than 12 metres

  • Ultimate spread wider than 8 metres

  • Time to ultimate height 20-50 years

How to grow

Cultivation Grow in moist, well-drained preferably neutral to acid soil in sun or part shade. Tolerates dry, alkaline soil. Further magnolia cultivation advice

Propagation Propagate by seed in autumn, semi-ripe cuttings from late summer to early autumn or layering in early spring

Suggested planting locations and garden types Wall-side Borders Low Maintenance Architectural

How to care

Pruning Pruning group 1 in spring as growth begins. Pruning group 13 in summer if wall trained

Pests May be affected by horse chestnut scale and capsid bug

Diseases Coral spot and honey fungus may be a problem

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