Allamanda (al-uh-MAN-da) is a perennial flowering plant commonly pruned into an evergreen shrub that belongs to the genus Allamanda and is a member of the family Apocynaceae (a-pos-ih-NAY-see-ee).
The genus Allamanda was named after Dr. Frederick Allamand, a Swiss botanist.
This evergreen creeping shrub is native to the tropical regions of South and Central America and is most abundant in Brazil, Suriname, Guyana, Argentina, and Mexico.
There are 15 Allamanda species, and many are widely cultivated as ornamental plants in tropical and subtropical areas of the world.
Among these many cultivars, the most popular species in the horticultural trade are:
- Allamanda Cathartica
- Allamanda Blanchetii or Allamanda violacea
- Allamanda Schottii
Allamanda is well-known for its distinguishing features of large, yellow flowers with a shape that resembles a bell or the musical instrument trumpet and large, glossy green leaves.
This tropical clambering shrub blooms year-round and is commonly planted in the spring, making it a great flowering houseplant in gardens, parks, and even indoors.
Allamanda flowers are also often visited by butterflies, bees, and sunbirds.
Allamanda goes by several common names, such as:
- Yellow Allamanda
- Common trumpet vine
- Golden trumpet
- Yellow bellflower
- Yellow bell
- Buttercup flower
Quick Facts On Allamanda Plants
- Family: Apocynaceae
- Light: Full sun, partial sun/shade
- Temperature: 70° degrees Fahrenheit
- Water: Keep soil moist but well-drained
- Fertilizer: Balanced fertilizer – 10-10-10
- Propagation: Stem-tip cuttings
- Common Problems: Damaged leaves. Aphids, Mealybugs, Thrips
Allamanda Plant Care
How Big Do Allamanda Plants Grow?
Allamanda plants are vigorous perennial vines, reaching their mature size of about 10′ to 20′ feet.
Their wines reach a maximum plant spread of about 3′ to 6′ feet, especially in sunny locations.
Although sometimes referred to as invasive because of their expansive spread, Allamanda vines could be trained against a trellis or other support structure and contained by pruning.
When Does Allamanda Plant Flower? Are The Flowers Fragrant?
Allamanda produces a rich cluster of yellow trumpet or bell-shaped flowers that consist of 5-lobed petals overlapping one another with a diameter of about 5″ inches across.
These dramatic yellow blossoms flare widely and emerge at the tip of new sprouts with a white blotch in the throat.
Most Allamanda species showcase bright yellow flowers, but other cultivars produce a variety of colors, including pale yellow, dark purple to white.
This evergreen clambering vine has lovely foliage of 2 to 4 large, glossy and leathery oblong-shaped leaves, growing up to 4″ to 5″ inches long and 1″ to 2″ inches wide.
The smooth-edged leaves are arranged in whorls along a woody twisted stem containing milky sap.
Allamanda blossoms mainly in the summer and fall season and flowers freely all year-round. It’s also prized for its fresh floral fragrance.
What Are The Lighting Needs And Temperature Requirements?
Allamanda thrives in full sun to bright partial shade spots and is best suited to tropical, sub-tropical, or monsoonal climate zones.
The Allamanda plant requires at least 70° degrees Fahrenheit or higher during the day and 60° to 65° degrees Fahrenheit during nighttime.
It also needs high humidity of at least 50% percent to blossom bountifully, especially in the blooming season.
Although this tropical plant appreciates plenty of sunshine and warmth in their vines and on the tips of their shoots, their roots relatively flourish in cooler areas.
So, they are preferably grown in a partial shade location but facing adequate sunlight.
It’s also best to surround the Allamanda with other plants for essential shading.
Allamanda plants grow in hardiness zones 10 and above.
They also don’t tolerate cold temperatures and will not blossom without adequate warmth and humidity.
When exposed to freezing drafts, their leaves drop.
During the late winter, it’s recommended to move the Allamanda plants indoors, especially if the climate plunges to a freezing temperature below 40° degrees Fahrenheit.
How And When To Water And Fertilize Allamanda?
Your allamanda plant requires regular watering and fertilizer feeding during the growing season to ensure a prolific bloom and prevent flower loss.
It’s also good to mist the allamanda plant every other day to supply the necessary humidity and moisture.
Fertilizing the allamanda plant is best with nitrogen fertilizer, liquid water-soluble plant food, or 10-10-10 balanced fertilizer every 2 to 3 weeks from spring through summer.
Make sure to maintain organic matter, such as compost, sawdust, grass clippings, or paddy straw around the base of the plant.
In the winter months, reduce watering but don’t let the roots dry out. Also, cut the fertilizer feeding to once a month instead.
What Is The Best Soil For Allamanda And When Should You Transplant?
Allamanda plants are best grown in fertile, organic, and moist soil with excellent drainage.
The ideal soil type is proportional chalk, clay, loam, and sand and must be acidic, alkaline, or neutral soil with a PH balance of 5.5 (strongly acidic) and 6.0 (acidic).
When transplanting, remember to do these following steps:
- Choose a well-drained area positioned in full sun.
- Make sure to enrich the soil with organic compost to enhance the soil texture.
- Dig the soil using a shovel and loosen it before planting.
- Remove the allamanda plant and gently loosen the root strands with your fingers.
- Plant the plant and gently firm the peat soil down.
Does Allamanda Special Grooming Or Maintenance?
Allamanda plants are vigorous and can grow rapidly, so pruning them every year is essential to keep them in control and allow new growth.
It’s best to prune them by trimming stems and deadwood in the early spring as the plant grows.
It can be pruned every year, and it is best done before the spring of the year when the plant grows.
Once the allamanda plant reaches maturity, pruning will not be required as much.
However, allamanda plants exude a poisonous, milky sap, which can cause skin irritation in some people, so be careful when pruning them.
How To Propagate Yellow Allamanda?
Yellow Allamanda is one of the easiest flowering plants to grow through propagation via softwood or hardwood stem tip cutting.
It’s best to propagate them in the spring, fall, or during the growing season.
Here are the tips to remember during propagation:
- Clip 6″ to 8″ inches long cuttings from the fresh growth shoot.
- Dip the cuttings into a rooting powder.
- Insert the allamanda cuttings in a container filled with porous fertile soil.
- Place them in a warm and humid environment.
- Water them enough to moisten the peat soil.
The new growth will emerge for about 3 to 4 weeks and will be ready for potting.
Golden Trumpet Pests And Disease Problems
Golden Trumpet is prone to pests and diseases, including:
- Aphids
- Mealybugs
- Spider mite
- Plumeria Caterpillars
- Thrips
So it’s necessary to keep an eye out for any signs of infestation of the following:
- Damaged or wilted leaves and dropping shoots (caused by lack of water)
- Chlorosis or yellowing or green leaves (caused by damaged roots)
- Stunted growth or brownish spots (caused by aphids)
Treat the infestation with insecticidal soap or pesticide every week until there are no insects left. Make sure to follow the product label instructions.
Golden Trumpet Uses
The golden trumpet is an evergreen tropical climbing shrub with bright yellow trumpet flowers that is easy to grow and blooms freely year-round.
They are often used as:
- Ornamental plant decoration for Mediterranean-type gardens.
- Ideal woody vine over pergolas, trellis, or other horizontal support structures.
- Effective ground cover in gardens.
However, all parts of the golden trumpet plants are highly toxic because of their milky sap and may cause irritation or allergic reactions to some people, so it’s also best to handle them with precaution.