Allamanda Guide: How to Grow & Care for “Golden Trumpet”

Our Guide to Allamanda - Everything you will ever need to know! Tips for growing and caring for “Golden Trumpet”

If you feel that your garden lacks some bright-coloured and summer-through-fall blooming plants, Allamanda will surely meet all your expectations! Besides their magnetic aura, these flowering plants are relatively easy to grow, care for, and also propagate. Now let’s get more familiar with them! Keep reading to find out more about these irresistible flowers.

Allamanda is a genus that contains about 12 to 15 accepted species of flowering plants in the Apocynaceae family. The adorable flowers from this genus are native to the Americas, being widely distributed from Argentina to Mexico. They grow mostly in abandoned yards, roadside ditches, dumps, and have also become an invasive species in some areas. But that doesn’t mean that they don’t deserve our attention.

Although all Allamanda species are worthy of our admiration, the most popular ones in cultivation are A. blanchetii (Golden Trumpet), A. cathartica (Purple Allamanda), and A. schottii (Bush Allamanda). These particular species are very common landscape adornments in the tropical and subtropical regions worldwide.

 About Allamanda

  • Depending on the species, the plants from the Allamanda genus go by various common names including Golden Trumpet, Yellow Bell, Bush Allamanda, Yellow Allamanda, Purple Allamanda, Common Trumpetvine, or simply Allamanda.
  • Allamandas come with interesting cultivars to choose from, such as ‘Grandiflora’, ‘Hendersonii’, ‘Flore Pleno’, and ‘Williamsii’. While the first and the last specimens feature single or double yellow flowers, ‘Hendersonii’ has golden single blooms and ‘Flore Pleno’ double white ones.
  • Allamanda plants look absolutely beautiful as additions to many landscape decorations, such as hedges, fences, borders, beds, patios, or decks. They also make for stunning potted, foundation, and accent flowers.
  • They play a big role in traditional medicine, having different health benefits. A. cathartica works as an excellent treatment for malaria, jaundice, liver tumours, and splenomegaly. Some species are also considered effective for treating HIV and fungi.
  • Besides their ornamental and medicinal purposes, Allamanda plants also enjoy cultural importance. They are the official flowers of Kuching North City Hall, in the state of Sarawak, Malaysia.
  • All parts of the Allamanda plants are pretty toxic to both humans and animals. Ingesting them can lead to mild symptoms of fever, thirst, or digestive issues. If touched, however, the eye and skin irritation will last only a few minutes.
  • Thanks to their stunning appearance and easy-going style, Allamandas are great companion plants to a wide diversity of species. The most common include Croton, Gold Mound, Green Island Ficus, Hibiscus, Panama Rose, Plumbago, and Ruellia.
Allamanda Flowers
Allamanda Flowers

Allamanda Features: An Overview

  • Allamandas are evergreen perennial flowering shrubs, vines, or trees, with some specimens having a climbing habit. Depending on the species, these plants can reach from 4 to 20 feet (1.2-6 m) in height and 3 to 10 feet (0.9-3 m) in width.
  • Their foliage consists of simple, leathery/slightly hairy, oval-shaped, smooth-edged, and bright green leaves that appear on long, thick, and woody stems. The leaves grow in whorls or oppositely arranged in pairs of up to 5 components.
  • The blooming period of Allamanda plants usually lasts from summer through autumn. While most species produce single or double blossoms, some others will exhibit numerous delicate and colourful clusters.
  • Their attractive trumpet-shaped flowers can measure between 2 and 5 inches (5-12 cm) in diameter. They typically have five petals and come in different shades of yellow, white, and pink to rose-purple.
  • Once their flowering season has ended, Allamandas bear fruits right where their blooms were before. The fruits are dry, spiny schizocarps that contain two to four seeds. They split open at maturity, releasing the seeds at considerable distances.

Growing Allamanda

Allamanda plants have a popular reputation for being very picky and unforgiving when it comes to their environmental and growing conditions. But there’s no need to worry or to avoid them! If you pay attention to their basic demands, you and these beauties will be best friends for a long time. At the end of the day, every living being needs a bit of love and attention to thrive. And it is only natural!

One of the most important factors that contribute to the well-being of Allamandas is, of course, lighting. In general, adequate sunlight will help them bloom profusely. These flowers prefer bright, strong indirect light, but they can also adapt to full sunlight exposure. In outdoor settings, grow your Allamanda plants in a location where they can receive lots of morning sun. Indoors, we suggest you place them in front of an east-facing window.

Dwarf Yellow Compact Allamanda Vine Plant, From Amazon

In terms of temperatures, Allamandas are usually hardy only in the USDA zones 10 to 11. These plants do well in daytime temperatures of 65 to 80 °F (18-27 °C) and 59 to 65 °F (15-18 °C) at night. As a general rule, they will not tolerate temperatures that drop below 59 °F (15 °C). In regions with cool weather, you should grow your flowers in a conservatory, greenhouse, or indoors. Moreover, it is wise to protect them from cold drafts mostly during the chilling months.

Allamandas are pretty vulnerable to pests, especially when we are talking about mealybugs and aphids. If you want to know whether your plants deal with an infestation, you should first look at their foliage to see if it is healthy or damaged. In positive cases, make sure you treat your buddies with insecticidal soap once every week until the intruders are no longer there.

Planting Allamanda

Allamanda plants will have the time of their life if you manage to plant them in a suitable growing medium. These plants will grow at their best in an acidic, peat-based potting soil that is rich in nutrients and organic matter. Likewise, you must plant them in a substrate that comes with excellent drainage. If you want to grow your flowers in pots, look for those that have drainage holes at the bottom or, otherwise, make them yourself.

Allamanda plants might seem very independent at the first glance, but they secretly dream about you giving them all your time and effort to make them happy. Due to this, your Allamandas will benefit from regular fertilizing throughout their active growing period. Feed them with a weak liquid fertilizer once every two weeks from spring through fall. In winter, it is more than enough to apply fertilizers only once a month or so.

Golden Trumpet
Golden Trumpet

Because most Allamandas are loose climbing species, they require some extra support to grow properly. Outdoors, make sure you plant your beloved flowers near a fence or other tall species of plants. If you grow them in pots, provide them with any organic support.

Allamandas have a tendency to grow and spread like crazy, so you may need to repot them regularly. When they seem to outgrow their pots, this is the perfect time to take action. Remove your plants from their growing medium and transplant them in containers that are one size larger than the current ones. Also, do not forget about adding some support if necessary.

Watering Allamanda

Like most tropical species, Allamandas are big lovers of moisture. What makes these plants truly friendly is their ability to forgive you in case you over-water them, but only if you grow them in well-draining soil. How often you will water your flowers will depend directly on the region you live in, season, and weather.

During the summer months, you can water your Allamandas whenever the top layer of soil feels dry to the touch. Make sure you remove any extra water from their tray to avoid soggy conditions or waterlogging. Once the winter shows its chilling vibes, you must reduce the frequency of watering. However, you should not allow your plants to dry out completely.

Allamandas will not handle prolonged dry periods pretty well, but you can help them in a simple way. All you have to do is mist your plants once every two days or so to provide them with the needed humidity. During the cold winter, you can skip misting for good.

Propagating Allamanda

The easiest and fastest way to have more of these lovely flowers around is through propagation. Allamandas usually show nice propagation results if you are using stem tip cuttings. Moreover, to increase your chances of success, you must take the cuttings from fresh green shoots at the beginning of their growing season, usually in early spring.

Now that you have the Allamanda cuttings, dip their cut ends into a rooting hormone to help them grow faster. After this process, plant them in a container filled with fresh seed-starting potting mix. Place the pot in a warm, well-lit, and humid area. For optimal growth, provide the cuttings with some extra heat at the bottom.

With proper care, your Allamanda cuttings should develop a healthy root system in about one month or so. Once new growth emerges, you can transplant them in their permanent locations. Don’t forget to also plant a few cuttings in cute pots and gift them to your dear family members or friends!

In Conclusion

It is quite difficult not to love Allamandas, especially when they are so stunning, low-demanding, and versatile. After all, why would you even want to resist their natural charm? Believe us, they are worth all the time and effort you will invest in them! Once you have one of the popular cultivars around, you will know that you have won the lottery ticket!

Miruna is an experienced content writer with a passion for gardening. She is the proud owner of an outdoor rose garden and an indoor collection of tiny succulents. She bought her first succulent 10 years ago - an adorable Echeveria Setosa. Now she owns more than 100 succulents and cacti of different colors, shapes, and sizes. Miruna is a versatile writer and, as you might have guessed, her favorite topic is gardening. Contact

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