Golden trumpet
Allamanda cathartica
Golden trumpet (also sold as yellow allamanda or common allamanda) is a fast-growing evergreen scrambling shrub in the dogbane family (Apocynaceae), native to northern and central South America: Kew's World Checklist places it in Brazil, Bolivia, Venezuela, Guyana, Suriname, and French Guiana. It carries clusters of large, golden-yellow trumpet flowers 3 to 4 inches long from summer until frost over glossy, leathery leaves held in whorls of three or four, and left alone it sends out long, woody, sprawling stems that reach 10 to 20 feet over a support or neighboring plants. It has no tendrils or aerial roots, and sources disagree on whether the stems twine, but both the Missouri Botanical Garden and NC State say it has to be tied or trained onto a trellis; it can also be pruned as a shrub or hedge. It is frost-tender and hardy only in USDA zones 10a-11b; everywhere colder it is grown as a summer annual or as a container plant brought indoors for winter. Two cautions matter as much as the flowers. It is invasive in several warm regions: UF/IFAS rates it a High Invasion Risk in north, central, and south Florida and does not recommend planting it, the Queensland Government's Weeds of Australia treats it as an environmental weed spreading through the rainforests of northern Queensland, and the Hawaii-Pacific Weed Risk Assessment rates it High Risk. And it is poisonous: every part is toxic if eaten, and the milky sap irritates skin and eyes.
Climate fit: narrow (13/100)
Focal point
Container
Structure
Light
Full sun
Water
Moderate water
Mature size
10-20 ft tall · 3-6 ft apart
Hardy in zones
10a-11b
mild to nearly frost-free winters
Life cycle
Perennial
Native in Illinois
No
Poisonous; not a food plant.
Cold hardiness
These values are location-based: this location's current hardiness is the baseline, and the 2050 value is a projected future climate for this same location.
Now
Zone 6b
Plotwright
USDA Zone 6b
-5°F to 0°F
Won't grow here
Zone 7a
Plotwright
0°F to 5°F
Won't grow here
In plain terms: This location has cold winters. Its winters are projected to keep warming through 2050.
✕
Out of range today and still out of range in 2050.
Heat tolerance
Heat tolerance values are location-based too: heat days today are observed at this site, and the 2050 value projects this same location under a future climate.
Loading AHS heat-zone data for this location...
Plant this, not that
Better fit for this place
For Chicago, IL, these are replacement suggestions: similar plants with a stronger hardiness fit now and/or in 2050.
Better fit now and in 2050
Now: well-suited
2050: well-suited
Better fit now and in 2050
Now: well-suited
2050: well-suited
Better fit now and in 2050
Now: well-suited
2050: well-suited
Better fit now and in 2050
Now: well-suited
2050: well-suited
Similar plants
Browse lateral options with similar roles, light needs, size, or native-range overlap; these are not filtered for a better climate fit.
Educator packet
Plant packet
Golden trumpet educator packet
Golden trumpet (also sold as yellow allamanda or common allamanda) is a fast-growing evergreen scrambling shrub in the dogbane family (Apocynaceae), native to northern and central South America: Kew's World Checklist places it in Brazil, Bolivia, Venezuela, Guyana, Suriname, and French Guiana. It carries clusters of large, golden-yellow trumpet flowers 3 to 4 inches long from summer until frost over glossy, leathery leaves held in whorls of three or four, and left alone it sends out long, woody, sprawling stems that reach 10 to 20 feet over a support or neighboring plants. It has no tendrils or aerial roots, and sources disagree on whether the stems twine, but both the Missouri Botanical Garden and NC State say it has to be tied or trained onto a trellis; it can also be pruned as a shrub or hedge. It is frost-tender and hardy only in USDA zones 10a-11b; everywhere colder it is grown as a summer annual or as a container plant brought indoors for winter. Two cautions matter as much as the flowers. It is invasive in several warm regions: UF/IFAS rates it a High Invasion Risk in north, central, and south Florida and does not recommend planting it, the Queensland Government's Weeds of Australia treats it as an environmental weed spreading through the rainforests of northern Queensland, and the Hawaii-Pacific Weed Risk Assessment rates it High Risk. And it is poisonous: every part is toxic if eaten, and the milky sap irritates skin and eyes.
Scientific name
Allamanda cathartica
Plant type
shrub
Hardiness
10a-11b
Light
full-sun
Moisture
moderate
Spacing
3-6 ft
Classroom prompts
- Which plant traits are observations, and which are care recommendations?
- How would this plant fit change if the garden location moved warmer, colder, wetter, or drier?
- Which source-backed facts would you cite in a lesson handout?
Use the Sources & citations section below for page citation styles and the field-level source list.
Sources & citations
Cite this page
For lesson plans, articles, or research that uses this page. Use the source cards below to explore the references that informed this record.
Plotwright. (2026, May 17). Golden trumpet (Allamanda cathartica). Retrieved 2026, October 9, from https://plotwright.com/plants/allamanda-cathartica
Sources used for this record
This record is compiled from the sources below.
UF/IFAS Assessment of Non-Native Plants in Florida's Natural Areas: Allamanda cathartica
University extension service
Environmental Weeds of Australia, Biosecurity Queensland edition (Queensland Government): Allamanda cathartica
Botanical research database
Hawaii-Pacific Weed Risk Assessment (Plant Pono): Allamanda cathartica
Botanical research database
UF/IFAS Extension Sarasota County: the all-too-troublesome allamanda
University extension service









