How to Grow Allamanda cathartica Plants in your Garden

Gardener's HQ Guide to Growing Golden Trumpet

Allamanda cathartica is a woody evergreen, tropical bush vine. It is often called by its common moniker, Golden Trumpet.

This vining plant boasts deep yellow trumpet flowers spanning 5 inches (12 cm).

Allamanda cathartica flower trumpets
Allamanda cathartica flower trumpets image by Forest and Kim Starr; CC.

It blooms consistently through the summer and into the first frost of fall in typical conditions; but can bloom all year in a tropical environment.

The foliage appears as bright green, leathery leaves that grow up to 4 - 6 inches long (10 to 15 cm).

Golden trumpet
Allamanda cathartica (Yellow allamanda) photograph by Forest and Kim Starr.

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.

Golden Trumpet Plant
Golden Trumpet plant, photograph by Forest and Kim Starr; CC.

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 Details

  • 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
  • Fruit:
  • 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

Caring Conditions

  • Care:
  • 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
  • Diseases: scale, leafspot

Further Information

  • Can Attract:
  • Tolerant of: Heat, high humidity
  • Best Garden Use: Arbor, Container, Specimen
  • Family: Apocynaceae.
  • Closely Related Species: Dogbanes: Adenium, Amsonia, Asclepias, Nerium, Pachypodium, Wrightia, Vinca

  • Miscellaneous: Attractive foliage, Non-native to North America, Some parts are poisonous, Fragrant flowers, Blooms are very showy
  • Genus Detail: Allamanda
  • Further Reading and References: Here and Here

Allamanda cathartica flowers and leaves
Allamanda cathartica, image by Forest and Kim Starr; CC.

I hope that you enjoyed this guide on how to grow Allamanda cathartica. You may also enjoy the following Gardener's HQ growing guides: How to grow Catharanthus and Vinca minor plants.