Allamanda cathartica 'Hendersonii'

RHS Plant Profile

golden trumpet 'Hendersonii'

John Fielding

Conservatory Greenhouse Climber Wall Shrub

A strong-growing, tropical, evergreen climber with whorls of 3-4 glossy lance-shaped leaves. In summer and autumn it bears golden yellow flowers to 13cm across that open from bronze-tinted buds. Grow in a large pot in a conservatory

Position

Full sun

Soil Types

Loam

Max Height

4-8 metres

Max Spread

4-8 metres

Size

Time to Maturity: 5–10 years
Max Spread: 4-8 metres
Max Height: 4-8 metres

Growing Conditions

Loam

Moisture: Moist but well–drained
pH: Acid or Alkaline or Neutral

Position

Full sun

Aspect: East–facing or 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): H1B

Colour & Scent

Season	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family: Apocynaceae
Native to GB/Ireland: No
Foliage: Evergreen
Habit: Climbing
Potentially harmful: Harmful if eatenskin and eye irritant. Wear gloves and other protective equipment when handling Pets (dogs, cats): Harmful if eatenskin and eye irritant - see the HTA guide to potentially harmful plants for further information and useful contact numbers
Genus: Allamanda are evergreen shrubs, sometimes scrambling, with simple, often whorled leaves and terminal clusters of large trumpet-shaped flowers
Name Status: Accepted

How to Grow

Cultivation

Under glass, grow in peat-free, loam-based compost in full light. Water freely in growth, applying a balanced liquid fertiliser every 2-3 weeks. Water sparingly in winter. Provide support for the climbing stems

Propagation

Propagate by seed sown at 18°C in spring, or by softwood cuttings

Suggested planting locations and garden types

Sub-tropical
Climber and wall shrubs
Conservatory and greenhouse

Pruning

Pruning group 11 or 12 in late winter or early spring

Pests

May be susceptible to glasshouse red spider mite and glasshouse whitefly

Diseases

Generally disease-free