Allamanda cathartica
Golden trumpet, Common allamanda, Buttercup flower
- Height × spread
- 8m × 16m
- Position
- Full sun
- Hardiness
- Frost free greenhouse 1C & above (RHS H2)
- Flowers
- Spring, Summer
Availability
Please ask in store about availability
Many plants are seasonal. Call 01234 567890 to check current stock.
About this plant
Grown for its spectacular trumpet flowers this makes a loose, not very clinging, twining plant which may be grown as a lax sprawling shrub. It has somewhat laurel-like light green oblong leaves. The huge flowers are bright yellow with flared mouths and orange streaking in their throats. This grows quickly and can, as a vine spread around 16 metres. It is tender, and cannot take cold or frost at all. It may need to be pruned for containment if grown within a conservatory. The sap is milky and irritating and the fruit is poisonous.
- Flower colour
- Yellow
- Foliage colour
- Green
- Variegated
- No
- Scent
- No
- Shape
- Fan
- Height
- 8m
- Spread
- 16m
- Flowers in
- Spring, Summer
- Evergreen
- Evergreen
- Garden style
- Conservatory
- Sun or shade
- Likes full sun
- Soil type
- Loam (normal)
- Soil pH
- Acid (ericaceous), Alkaline
- Drainage
- Moisture retentive soil, Well drained soil
- Hardiness
- Frost free greenhouse 1C & above (RHS H2)
- Borders & containers
- Borders
- Indoor light
- full light at all times
- Indoor temperature
- 7C minimum temperature
- Use for
- Structural
- Hazards
- Yes, potentially harmful; Humans: Harmful if eaten; skin & eye irritant
Spring
Spring-Autumn · Indoors
Feed with houseplant food monthly
Give the plant a balanced houseplant feed monthly while in growth.
Where food elements are listed as three numeric values on the label representing in order Nitrogen(N)-Phosphorus(P)-Potassium(K), with percentage values for each, choose one where the values are more or less equal.
Spring-Autumn · Indoors
Water regularly during growth
Water regularly while in growth.
Adopt a regime that means the plants are thoroughly watered every week so that they do not become dessicated. In hot weather watering may need to be more frequent, but less often in cool or moist conditions.
Spring - late · Outdoors
Feed with slow release fertiliser
Apply a general purpose slow release fertiliser, spreading it around the root area of the plant as it is coming into growth. (Or apply a liquid feed at regular intervals throughout the growing season.)
This is a simple way to provide a nutrient boost as a single annual procedure.
Spring-Autumn · Outdoors
Water regularly during growth
Water regularly while in growth.
Adopt a regime that means the plants are thoroughly watered every week so that they do not become dessicated. In hot weather watering may need to be more frequent, but less often in cool or moist conditions.
Spring-Summer · Planting
Prune after flowering
Remove any dead or damaged branches, or any growth that looks very untidy. Trim the plant back if necessary to keep it within bounds.
Winter
Winter-Spring · Indoors
Water lightly in winter
The soil should remain just moist during the cold months when the plant is not in growth. Trickle a little water onto the soil surface every couple of weeks if the soil is dry. Do nothing if it is moist.
The roots remain active in winter and benefit from small amounts of moisture so they don't become completely desiccated.
Winter · Outdoors
Water sparingly during dormancy
In its dormant period give very little water, keeping the soil barely moist. Dormancy is likely to be during the winter and the plant recommences growth in early to mid spring.
When a plant enters dormancy the leaves fade, go yellow and then brown. Eventually the whole plant may 'disappear' or unadorned stems may remain.
Planting & general
Outdoor planting · Planting
Add root growth stimulant to the planting hole
Mycorrhizal fungi helps roots establish quickly, so they absorb water and nutrients more efficiently. It comes as a powder, granule or gel. Add to the planting hole or container, and to the plant's rootball before planting in the hole. For "bareroot" plants use a gel.
Compost · Planting
Loam based houseplant compost for repotting
Buy container or house plant compost that is loam based if possible (i.e. is based on John Innes compost number 2 or 3. This contains more fertiliser and is better suited to established plants.
John Innes no. 1 has the lowest level of fertiliser and is used for seedlings and young plants, so is generally used where plants will be 'potted on' after a number of weeks.
Indoor temperature · Planting
7C minimum temperature
This plant requires a minimum temperature of 7 Centigrade.
Indoor plant · Planting
Position in a sunny spot, close to window
Give this plant a position where there is as much light and sunlight as possible, within 2-3 metres of a sunny or bright window (one that is south, east, or west facing).