The foliage appears as bright green, leathery leaves that grow up to 4 - 6 inches long (10 to 15 cm).
Allamanda cathartica can be trained to grow onto a trellis as a vine or pruned into a bush shape.
This woody climber can grow up to 10 - 20 feet tall (3 to 6 m) and 3 - 6 feet (0.9 to 1.8 m) wide. It is able to grow faster in warmer weather.
Gardener's HQ Allamanda cathartica Growing Guide
Grown best in hardiness zones 10 to 11, the Allamanda cathartica plant requires warm temperatures to grow and bloom properly.
It prefers full sunlight exposure but will tolerate partial shade.
Best grown in loamy or sandy soils, this plant requires a cooler temperature for its roots than its vines. It does well in fertilized, moist soils.
For optimum growth, the woody vine should be fertilized and watered regularly during its growing season.
Organic mulch is recommended for application around the base of the plant to keep the soil moist and at a lower temperature.
The vines only produce blooms on new growth, and pruning is recommended for the most cohesive look.
Allamanda cathartica may be cut back in early spring to ripe or half-ripe wood in order to stimulate more growth during the growing season.
Allamanda cathartica Growing and Care Guide
Scientific Name: Allamanda cathartica
Common Name: Golden trumpet
Growing Zone: USA: 9 to 11; UK H1b, Grow indoors, should be fine outdoors in a container in the summer.
Life Cycle / Plant Type: Vine, Shrub
Plant Height (Inches): 300 to 600
Plant Spread (Inches): 80 to 144
Time of Bloom: Mid summer to Mid fall
Flower Details: Yellow
Leaf Foliage: Green
Growth Form: Spreading or horizontal, Upright or erect, Variable spread
Ideal Growing Conditions
Best Light Conditions: Full sunlight
Rate of Growth: Quick
Suitable Soil Types: Adaptable, Clay, Loamy, Sandy, Well drained
Soil Moisture: Moist
Level of Maintenance:
Propagation: Seed or green wood cuttings
How to Prune: As a vigorous climber it is important to prune back flowers that occur on last years growth following flowering, while flowers on this years growth should be pruned towards the end of winter or in spring. Other than this no need to perform pruning except to keep plants tidy and confined.
Pests: CGlasshouse red spider mite and glasshouse whitefly