The Mandevilla Genus

The Mandevilla genus, known for its tropical vibes with often brightly-coloured trumpet flowers, comprises a group of flowering plants belonging to the family Apocynaceae.

Originating primarily in South America, these sun-loving plants are beloved around the world, especially in humid parts of Australia, for their showy blooms, climbing habit, and lush foliage. The genus includes over 100 species and numerous cultivars, commonly grown as ornamental plants for gardens, greenhouses, and containers.

Identifying Plants in the Mandevilla Genus

Mandevilla plants are identifiable by their climbing or twining growth habit and strikingly vibrant trumpet flowers. The leaves are typically glossy, dark green, and oval-shaped with a pointed tip, as opposed to the compound leaves of the native Australian trumpet-flowered Pandorea.

Flowers are the most eye-catching characteristic, ranging from white and pink to red and yellow, funnel-shaped with five petals, often exuding a delicate fragrance. Some species display a bushier form rather than climbing, but all share the hallmark tropical aesthetic.

Their growth habit is supported by a woody or semi-woody vine, ideal for trailing upwards along trellises, pergolas, or fences. You’ll often see pollinators like native bees and butterflies hanging around them; just because the plants are from another continent it doesn’t make them any less bountiful for our local wildlife!

Horticultural Characteristics

Mandevillas are highly favoured for their ornamental value. They thrive best in warm climates, requiring full sun to partial shade for best appearance and well-drained, fertile soil enriched with organic matter.

Whilst they enjoy warm tropical and subtropical regions, they can be overwintered indoors in cooler areas, where they are treated as tender perennials. We will mention two varieties shortly which have been bred for much better tolerance of frost than the common forms.

As vigorous climbers, some Mandevilla spp. can. be capable of growing 3–4.5 metres tall in a single growing season under optimal conditions. Regular feeding with a high-phosphorus fertiliser may encourage prolific blooming (where phosphorous is a limiting factor in the soil).

Deadheading or pruning can help maintain an orderly appearance and prolong flowering from spring through autumn. Their ability to thrive in containers makes them suitable for patios, balconies, and other positions with a somewhat limited root volume.

Ecological Contributions

Beyond their ornamental value, Mandevilla plants contribute ecologically by attracting pollinators like bees and butterflies, drawn to the nectar-rich flowers. Their dense foliage can provide shelter for small insects, contributing to biodiversity within a garden.

Even the sap-suckers that may appear have immense ecological value. In a healthy ecosystem, sap-sucking ‘pests’ provide a source of nutrition for the insects and animals that feed upon them, helping control populations and avoid unsightly outbreaks.

Common Problems in Landscaping

While Mandevillas are quite hardy in the right conditions, they are not without challenges. Common issues include susceptibility to pest infestations, particularly by spider mites, aphids, and whiteflies, which can damage foliage and flowers.

As mentioned above, these ‘pests’ are a food source for higher organisms, but if they become unsightly a quick spray with white oil (made from vegetable oil, detergent and water) will smother them with minimal impact to the wider ecosystem.

They are also prone to fungal diseases like powdery mildew or root rot, but avoiding overwatering or poor drainage tends to solve this issue. Keeping the microbiome healthy also helps, so make sure the soil is happy with some organic matter; a bit of liquid seaweed feed can also give the plant a health treatment to help the fight against pathogens before they do too much damage.

Additionally, their sensitivity to colder temperatures can lead to leaf drop or plant death during unexpected frost spells. Careful monitoring and protection during cold snaps are essential when growing them in cooler climates. Below, you’ll see two varieties that are much more tolerant of frost than the common types, even thriving in sheltered positions in the ACT.

All Seasons Red™

Mandevilla spp ‘MAND01‘ PBR Intended Trade Name All Seasons Red™

If you’re looking for a dense climber, or even an upright shrub without support, with some of the most vibrant red flowers you’re likely to see, this is your best option. While it loves heat and humidity, it tolerates frost surprisingly well for a Mandevilla and has an improved growth habit closer to ideal ratios.

All Seasons Pink™

Mandevilla spp ‘MAND02‘ PBR Intended Trade Name All Seasons Pink™

This pink-flowered variety is almost identical to the previously-mentioned red-flowered variety, but with pink blooms. With its improved growth habit, it brings tropical vibes to cooler climates that, until now, have been unable to rely on plants within the genus.

Daniel’s Wrap

The Mandevilla genus offers a spectacular visual appeal, transforming gardens or interior spaces into bursting displays of tropical colour. Their climbing habit, sturdy growth, and showy blooms make them a favoured choice for gardeners seeking dramatic yet manageable plants.

ith proper care and monitoring for common issues, Mandevilla can provide long-lasting beauty and economic value to any landscape. Remember that not all Mandevilla plants are equal. Opt for one of the tried and tested varieties above that have been bred for higher performance in both heat and cold.