Dipladenia (Mandevilla) are climbing shrubs from the family of dog poison plants (Apocynaceae). They come from the jungle of South America and have been popular with us for over 100 years as pot and tub plants. Almost the whole summer the wonderful white, pink, red or yellow flowers of the evergreen climbing plants decorate balconies and terraces. Frequently, the plant called today mostly Mandeville (named after Henry John Mandeville) is also still listed under its older botanical name “Dipladenia”. More than 120 species of dipladenia are known. Most of the plants we cultivate are small hybrids of the wild species Mandevilla sanderi, into which other species such as Mandevilla splendens or Mandevilla boliviensis have been crossed. A special outdoor form is Mandevilla laxa, also known as Chilean Jasmine, with greater tolerance to cooler temperatures and white flowers.
Appearance and growth
The evergreen dipladenias are fast-growing climbing shrubs, which, with sufficient food, wind their way up quickly. Depending on the variety, the liana-like climbers can reach up to six metres. For balcony and window sill often compressed breeds are offered in the trade. They remain small and compact through artificial containment of the growth urge – but often only in the first year. At the latest after hibernation in the second year, when the upsetting agent has lost its effect, they shoot noticeably upwards.
The shiny dark green leaves of the Dipladenie stand on short stems and are slightly hairy. The leaves contain impalpable glands. White latex escapes from them when leaves and stems are damaged. It tastes bitter and is slightly poisonous. The five sepals of the Mandevilles open to a funnel-shaped flower of up to five centimeters in size in the colours white, yellow, violet and various shades of red. Dipladenias bloom from May to autumn, forming new buds throughout the summer. New cultivars show an impressive abundance of flowers. The white flowers of the winter-green Mandevilla laxa also exude a pleasant scent. The pollination takes place mainly through bees and bumble bees, in its tropical homeland also through hummingbirds.
After flowering, capsule fruits with elongated, hairy seeds appear on the inside of the plants. For a greater abundance of flowers, you should remove ripening fruit, which saves the plant unnecessary energy consumption.
Location and substrate
The different types of Dipladenia are suitable for balconies or terraces as well as for warm conservatories. Mandevilla laxa can also stand in the cold winter garden. In order to flower richly, the frost-sensitive beauties need a lot of light in any case. Place the plants in a very light, humid place where they are protected from the blazing midday sun in the best case, as dipladenias react somewhat sensitively to this. Mandevilla thrives in sufficiently warm semi-shade as well, but the flowering is a little less. Temperatures around 20 degrees and more are ideal for tropical climbing plants. Dipladenias are best planted in high-quality potted plant soil, whereby they also tolerate slightly acidic, alkaline or calcareous substrate.
The water requirement of a dipladenia is moderate. In its thick leaves and storage roots, the plant can hold water for a long time. Always water the climbing plant so that the root ball is well moistened but not wet. Make sure that excess water can drain off immediately to prevent waterlogging. Only use tempered water with as little limescale as possible. Keep the root ball evenly moist throughout the growth period and spray the plants more often. After flowering, watering is reduced. To ensure that the climbing plants thrive well, you should provide them with a high-quality liquid pot plant fertilizer once a week. Since Mandevillen are climbing plants, they need a climbing aid in the pot. Every two to three years in spring, when the ball of the pot is completely rooted, the plants are re-potted into a slightly larger pot. Larger dipladenias also tolerate it well if the root ball is simply reduced in size and put back in the same pot with fresh soil. When repotting, you should add some slow-release fertilizer to the substrate.
Smaller pruning work on the plant can be done all year round. However, the Mandevilla blooms on the new shoot, so you should not cut too generously later in the season. Plants that have become too large or misshapen and need more pruning are best pruned in late winter (February/March). At this time a pruning stimulates new shoots and thus flower formation. Dipladenias also do not take a pruning close to the ground crooked – in spring the plants sprout vigorously again. Young plants should be de-ricked more often for bushy growth. To stop the strong flow of latex, you can then immerse the shoots in water or spray them with water.
Cutting tool in the our store-Shop
With the exception of the Mandevilla laxa, the exotics are very sensitive to cold. Therefore, they are put into a bright, 5 to 12 degrees warm winter-quarter still before the first frost. If they are wintered cool, the Dipladenien take a rest from October to March. Then they should also be watered less, so that the root ball can dry off in between. If they stand in the dwelling or heated winter garden with over 20 degrees, they are cared for as usual and bloom then also in the winter further. In contrast to all other species, the Chilean Jasmine (Mandevilla laxa) tolerates frost temperatures of up to minus five degrees Celsius for a short time. Nevertheless, it should only be wintered outside in very mild locations with good frost protection. Ensure sufficient humidity in winter quarters and ventilate on frost-free days. In May, after the last late frosts, the potted plants are allowed to go outside again.
The reproduction of the Mandevilla at home is a matter of luck, because the rooting rate is not very high. If you still want to try it, you can cut head cuttings about ten centimeters long from the tips of the shoots, remove all but one pair of leaves, dip them in rooting powder and then put them in an earth-sand mixture or cultivar soil. The pots are poured on, covered with a transparent foil bag and not opened for the time being. Alternatively, a well-closing mini greenhouse can be used. With heat (well over 20 degrees) and a lot of light, for example on a window sill above a heater, the cuttings form new shoots after a few weeks. Now patience is required: The plastic hood is ventilated daily for a few months until several young shoots appear. Once the small plant has regrown vigorously, it can move to a larger pot without a hood. In early summer, dipladenia can also be increased by lowering. For this purpose, a long, slightly woody shoot in the middle section is freed from the leaves and its bark is lightly scratched. In addition to the mother plant, the shoot section prepared in this way is sunk into the soil. Tip: The branch can be anchored perfectly in the ground with a hairpin. The shoot tip should be on the other end of the earth. Here, too, successful rooting is evident in the strong new shoots.
More climbing plants in the our store-Shop
Species and varieties
Especially drought-resistant varieties are the Mandevilla Sanderi hybrids ‘Sundaville’ and ‘Tropidenia’. Some compact varieties from the ‘Jade’ series are ideal for the balcony box. Climbing species such as the Chilean Mandevilla (Mandevilla boliviensis) are ideal for climbing trellises or scaffolding and are well suited as privacy screens. Small varieties such as ‘Diamantina Jade White’ are ideal for hanging baskets. The pink Mandevilla x amabilis ‘Alice du Pont’ with flower funnels up to ten centimeters in size is considered the largest dipladenia. It is fast-growing and forms metre-long shoots, which are guided along the climbing frame. The Mandevilla hybrid ‘Sundaville Red’ feels at home in the heat, tolerates dryness and adorns itself with velvety red flowers throughout the summer. It is pulled on climbing frames and is about 150 centimeters high.
Diseases and pests
Dipladenia are not particularly stress-resistant. They are particularly susceptible to pests such as the white fly in persistent heat and drought. Yellow boards can be placed around the plant as a precaution, in case of heavy infestation pesticides must be used. At the beginning of May, aphids frequently appear on the leaves. Too dry air can lead to rolled leaves. In the winter-quarter, the Dipladenie is frequently populated by wool-lice. In the case of very severe pest infestation, the plant should simply be radically pruned back in late winter.
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I am Don Burke, one of the authors at My Garden Guide. I am a horticulturist that cultivates, grows, and cares for plants, ranging from shrubs and fruits to flowers. I do it in my own garden and in my nursery. I show you how to take care of your garden and how to perform garden landscaping in an easy way, step by step.I am originally from Sydney and I wrote in local magazines. Later on, I have decided, more than two decades ago, to create my own blog. My area of specialization is related to orchid care, succulent care, and the study of the substrate and the soil. Therefore, you will see many articles dedicated to these disciplines. I also provide advice about how to improve the landscape design of your garden.