Mandevilla, also known as Dipladenia, Brazilian jasmine and rock trumpet, is a woody climber native to tropical Central and South America. It has gently scented, vibrant blooms and makes a fine conservatory plant in the UK.
The name ‘Mandevilla’ is derived from the surname of a British diplomat and plant enthusiast named Henry Mandeville (1773-1861). While Mandeville didn’t directly discover or introduce the plant, the name was given in his honour by the botanist Charles Hamilton, who named the genus after him.
Mandevilla plants are evergreen, so they do not lose their leaves in winter. However, they may experience some leaf-drop if exposed to cooler temperatures.
Bear in mind that mandevilla is toxic to dogs and cats, and can lead to stomach upset, nausea and vomiting if ingested.
How to grow mandevilla
Grow mandevilla in a sunny, humid spot such as a heated greenhouse or conservatory, in free-draining soil or a large pot of loam-based compost with added grit to aid drainage. Train it up a trellis or obelisk to make the most of its fragrant blooms.
Where to grow mandevilla
Humidity is key to successfully growing mandevilla – spring conditions should be humid with an average day time temperature of 21ºC and a night time temperature no lower than 18ºC. Winter temperatures shouldn’t fall below 15ºC. The best places to grow mandevilla are therefore conservatories and heated greenhouses, where conditions best mimic their natural tropical environment.
If possible, grow mandevilla direct in the soil of a greenhouse or conservatory border. Being a large, woody climber, it can struggle in pots.
How to plant mandevilla
For best results, plant mandevilla direct into the greenhouse or conservatory border, adding horticultural grit to the planting hole to aid drainage if necessary. Dig a hole slightly larger than the root ball, then place the plant in the hole, ensuring it’s at the same level it was in the original container. When you’re happy with the planting depth, backfill with the potting mix and gently firm the soil around the plant, and water thoroughly.
If planting in pots, choose as large a container as you can afford and plant into a loam-based compost such as John Innes No 3. Add horticultural grit to aid drainage.
After planting, choose three to five stems to make a permanent ‘framework’, which you can tie to your support. You will use this framework to prune around each year.
Caring for mandevilla
In spring and summer, water regularly and apply a monthly liquid feed in summer. Reduce watering in autumn and winter, and then increase again from spring. Mist daily in summer to increase humidity.
Pruning is essential to manage the size of mandevilla plants and promote healthy growth:
- If there is only one main shoot, trimming its length by one-third will stimulate further growth from the base – ideally you want three to five main shoots to create a permanent ‘framework’ that will make pruning easier in the long term.
- Remove overcrowded or weak shoots to maintain a compact and tidy appearance
- From late winter to early spring, spur prune stems by cutting back side shoots to within three or four buds of the permanent framework. This will encourage the development of flowering wood. Avoid pruning in winter, as this can weaken the plant
Propagating mandevilla
Mandevilla can be propagated by softwood cuttings or seed.
To take cuttings:
- Take a 15cm cutting from a healthy stem and remove the lower leaves
- Dip the cut end in rooting hormone and plant it in a moist but well-drained potting mix
- Keep the cuttings in a lidded propagator with bottom heat of 20-25ºC
- Cuttings should start showing signs of growth after around a fortnight. Pinch back the new growth to create a bushier habit
From seed:
- Soak mandevilla seeds in water for approximately twelve hours before planting
- Sow seeds in a later of moist, free-draining compost and cover lightly
- Place in a lidded propagator with temperatures ranging between 18-23ºC
- Pot seedlings into individual pots once there are are least two pairs of leaves per plant
Pests and diseases
Mandevilla can be susceptible to pests such as aphids, mealybugs and spider mites. To deal with these pests organically, you can use insecticidal soap, following the instructions on the packaging. Signs of infestation include discoloured leaves, sticky residue, or visible pests.
Advice on buying mandevilla
- Look for healthy plants with lush foliage and no signs of pests or diseases
- Choose plants with strong, sturdy stems and vibrant flowers
- Always buy from reputable nurseries or garden centres to ensure quality
- Opt for established plants rather than small seedlings for quicker growth and blooming
Where to buy mandevilla
Mandevilla varieties
Mandevilla ‘Bloom Bells ® Red’ – crimson blooms over a long flowering period. Height x Spread: 1.8m x 50cm
Mandevilla sanderi ‘Bloom Bells® White’ – bright white flowers against a backdrop of glossy, dark foliage H x S: 1.8m x 50cm
Mandevilla ‘Sundaville Flamingo Pink’ – unusual flamingo pink blooms. H x S: 1m x 50cm
from BBC Gardeners World Magazine https://ift.tt/1YucGLZ
