Buddleja tubiflora - The Fragrant Butterfly Bush

Tubiflora Butterfly Bush, Tubiflora Summer Lilac, Tubiflora Sweet Butterfly Bush, Buddleia Tubiflora

Want to add something rare and exotic to your garden or plant collection? Buddleja tubiflora, also known as Buddleja tubiflora Benth, offers a vibrant splash of orange with its striking tubular flowers and elegant form. Native to South America, this shrub is a botanical treasure, ideal for collectors or enthusiasts seeking less common species.

Buddleja tubiflora is a lesser-known flowering shrub native to parts of Paraguay and Argentina. This rare species belongs to the genus Buddleja, which includes many pollinator-friendly plants. However, Buddleja tubiflora sets itself apart through its unusual flowers and specific climate preferences.

First described by George Bentham, the plant is formally referred to as Buddleja tubiflora Benth. While many buddleias are commonly found in UK gardens, this one remains a rare sight. It’s typically cultivated by specialist growers and collectors who appreciate the uniqueness of South American species.

Unlike its more familiar relatives, such as Buddleja davidii, Buddleja tubiflora has a more delicate, upright form. It produces long, tubular flowers in vibrant orange shades—rare among buddlejas, which are usually lilac or purple.

Another defining feature is its floral cluster. The blooms are grouped into small, neat bunches rather than large panicles. This gives the plant a distinctive silhouette, making it a compelling choice for exotic or tropical-style plantings. Its compact form also lends itself well to container growing or display in a curated collection.

Botanically, Buddleja tubiflora is a deciduous shrub that typically grows to around 1.5–2 metres tall. It prefers warm, dry conditions and is naturally adapted to open, sunny areas in its native range.

Its leaves are slender and lanceolate, often with a slight silvery sheen. They offer a soft visual contrast to the vibrant flower spikes. As a plant, it is relatively slow-growing but can thrive under the right conditions, especially if its roots remain undisturbed and the soil is well-drained.

The main appeal of Buddleja tubiflora is its remarkable orange bloom. Each flower is long and narrow—hence the name “tubiflora”—and tapers gently into a flared mouth. The tubular structure of the flowers is ideal for attracting hummingbirds in their native habitat, although in the UK, it may also appeal to long-tongued bees and butterflies.

The flowers grow in compact clusters at the ends of the stems, creating a graceful and airy appearance. Some plants may show yellow tinges at the base of the flower tubes, adding depth to the overall colour display.

Yes, but it’s not as straightforward as with hardier buddlejas. Buddleja tubiflora is best suited for experienced gardeners or collectors who are comfortable working with tender or borderline hardy plants. Due to its sensitivity to cold and wet conditions, it’s typically grown under glass or in sheltered microclimates.

If you live in a warmer part of the UK with free-draining soil and a sunny south-facing wall, you may succeed outdoors. Otherwise, container growing offers better control and the option to move the plant indoors during winter.

Successful cultivation begins with replicating the plant’s native environment. Think dry, sunny, and well-drained. Use a soil mix high in grit or sand—something similar to what you’d use for alpines or succulents. Terracotta pots work well, as they allow for airflow and reduce the risk of root rot.

Water sparingly and avoid letting the roots sit in wet conditions. During the growing season, feed with a low-nitrogen fertiliser to support flowering rather than leafy growth. The plant benefits from occasional repotting but doesn’t like root disturbance.

Yes, winter protection is essential, particularly in the UK’s cooler, wetter climate. If you’re growing Buddleja tubiflora outdoors, you’ll need to mulch heavily around the base and cover the top growth with fleece or cloches. Raised beds or south-facing gravel gardens offer some natural frost resistance.

Alternatively, the safest method is to move the plant indoors before frosts arrive. A cool conservatory, unheated greenhouse, or cold frame can provide enough shelter. This approach reduces exposure to excessive moisture, providing the plant with the dry dormancy it needs.

The leaves of Buddleja tubiflora are generally disease-free, but they can show signs of distress in poor drainage or low light. Keep foliage dry and ensure good air circulation. During late autumn and winter, it’s normal for the leaves to drop as the shrub enters dormancy.

To maintain a balanced shape, prune in early spring once signs of growth return. Cut back any dead or weak stems. Because this species tends to grow upright rather than sprawling, pruning is often minimal and primarily for aesthetic purposes.

Absolutely—and in fact, this is the preferred method in much of the UK. Grown under glass, Buddleja tubiflora thrives in conditions you can carefully control. A greenhouse, conservatory, or even a sunny indoor windowsill can provide the warmth and dryness it needs.

Under glass, the plant often flowers more reliably, as it avoids the damage caused by UK winters. You’ll also enjoy more foliage and improved flower colour due to the higher light levels. Be sure to ventilate regularly to prevent fungal growth.

Yes, and it’s a fantastic candidate for specialist collections. Whether you’re curating a South American species garden, a butterfly- and bee-friendly zone, or a conservatory display, Buddleja tubiflora adds an exotic flair.

Its relative rarity adds interest to any collection. Botanical gardens in both the UK and Europe sometimes grow it in alpine houses or glasshouses for educational purposes. Collectors interested in expanding their range beyond common Buddlejas will find this plant a worthy challenge.

While I’m not currently growing Buddleja tubiflora myself, I genuinely admire its unique charm and delicate beauty. For gardeners looking to add something rare and exotic, it’s a rewarding challenge, especially for those with a greenhouse or a protected spot. I appreciate how its slender orange flowers and silvery leaves bring a subtle yet striking contrast to a collection, making it a standout specimen. Although it requires careful attention, particularly during winter, the payoff is well worth it for the interest and elegance it adds. If you’re passionate about unusual plants and don’t mind a bit of extra care, Buddleja tubiflora is definitely worth considering to bring a touch of South American flair to your garden.

• Buddleja tubiflora (also known as Buddleja tubiflora Benth) is a rare South American species
• Native to Argentina and Paraguay, it features orange tubular flowers in compact clusters
• This deciduous shrub typically grows to 1.5–2m and prefers dry, sunny conditions
• Best grown under glass in the UK, or in containers that can be protected in winter
• Requires well-drained soil, low water, and full sun for best results
• Sensitive to frost—must have protection in colder months
• Its leaves are slender and elegant, with good resistance to pests
• Minimal pruning is needed—just shape in spring and remove weak stems
• Ideal for exotic gardens or botanical collections
• Feed sparingly, and always prioritise drainage and warmth

Buddleja tubiflora thrives in a sheltered, sunny position with well-drained, sandy or loamy soil that has been improved for drainage. It tolerates a pH range of acidic, neutral, or alkaline. Hardy down to –8°C to –10°C (18°F to 14°F), it will grow 2–3 m (6.5–10 ft) tall in 5–10 years and flowers from July to September with unusual orange, tubular blooms. It is a unique addition for warm, protected UK gardens, needing annual improvement, winter mulching, and care with drainage, offering striking flowers and upright form through late summer.

Want to learn about other shrub varieties? Read about Buddleja Pink Delight here.

For more information on Shrubs for your garden, please click here.

Q: What is Buddleja tubiflora, and where does it originate?

A: Buddleja tubiflora, also known as Buddleja tubiflora Benth, is a deciduous shrub native to Paraguay and northern Argentina. This unusual species is prized for its long, trumpet-shaped orange to yellow blooms, which are typically borne in small clusters. The leaves are narrow, grey-green, and felted beneath, giving the plant an attractive, silvery appearance. Though relatively unknown in mainstream horticulture, it is increasingly sought after by collectors and enthusiasts for its rarity and ornamental value. As a non-hardy species, it is best grown under glass in cooler climates, making it a gem in specialist collections.

Q: How can I grow Buddleja tubiflora successfully in the UK?

A: To successfully grow Buddleja tubiflora in the UK, it’s advisable to keep the plant under cover—such as in a conservatory or greenhouse—especially through winter. This species requires bright light, warmth, and excellent drainage. Use a gritty compost mix and water sparingly in winter to avoid root rot. During the growing season, water regularly and feed monthly with a balanced liquid fertiliser. Prune lightly to maintain shape and encourage flowering. Although it may tolerate brief light frosts, long-term success depends on providing reliable winter protection, particularly from excess moisture and cold.

Q: When does Buddleja tubiflora flower, and what do the blooms look like?

A: Buddleja tubiflora produces slender, trumpet-like flowers from mid to late summer, depending on growing conditions. The flowers are a rich orange with hints of yellow, often appearing in small clusters that emerge from the tips of young growth. While not as showy as some ornamental buddleja hybrids, the blooms are elegantly shaped and highly attractive to pollinators. These exotic blooms contrast beautifully with the plant’s silvery leaves, adding textural interest to a greenhouse display or warm, sheltered corner. The unique floral form sets this species apart within the Buddleja genus.

Q: What type of plant is Buddleja tubiflora, and how large does it grow?

A: Buddleja tubiflora is a deciduous shrub, forming an airy, upright structure that can reach 1–2 metres in height when grown in ideal conditions. It is not considered invasive and remains well-behaved in cultivation. In cooler climates or when grown under glass, growth may be more compact. Its delicate, greyish leaves and tubular flowers give the plant a light, delicate appearance. While modest in size, it makes a striking feature in a specialist collection or botanical glasshouse, particularly when grown alongside other rare species from South America.

Q: Does Buddleja tubiflora require winter protection in the UK?

A: Yes, protection is essential when growing Buddleja tubiflora in the UK. Native to warmer regions of Paraguay and Argentina, it does not tolerate prolonged frost or cold, damp soil. It is best cultivated in pots and brought indoors before the temperature falls below 5°C. Alternatively, grow it year-round in a bright, frost-free greenhouse or conservatory. Avoid overwatering during colder months, and provide good air circulation to prevent fungal issues. With appropriate care and cultivation, this elegant plant can thrive for many years and reward you with its exotic summer blooms.

Q: Where can I buy Buddleja tubiflora in the UK?

A: Buddleja tubiflora is considered a specialist species and is not typically available at general garden retailers. However, it can be sourced from select nurseries that specialise in rare or exotic plants, particularly those with South American origins. A growing number of online suppliers now offer this plant, often listed under Buddleja tubiflora Benth. Availability may be seasonal, so it’s worth joining waitlists or contacting specialist growers directly. Some garden centres with niche collections may occasionally stock it. Always choose reputable sources to ensure healthy, correctly labelled plants.