One of my favourite show gardens in recent years was designed by Brendan Moar for the first Australian Garden Show Sydney. It won Best in Show but what really peaked my interest was how Brendan had incorporated Rhipsalis or mistletoe cacti, hanging them from the pergola to provide a weeping effect.
The garden was framed by an elegant black and white pergola; featured cascading water and a paved seating area – all skilfully and stylishly combined. I spoke to Brendan about the design and was interested to hear that the Rhipaslis plants had actually stimulated the design of the garden. A quote from the commentary:
“The hanging plants, suspended, floating and defying gravity are at the heart of the garden”.
Mistletoe cacti have made it central stage.
Rhipsalis and Lepismium are true cacti, however they do not conform to the imagined cliché – the clustering or tree-like plants that grow in deserts. Instead they generally grow as epiphytes upon trees. These are plants that grow on branches or among mosses and do not parasites or harm their hosts in any way. A few species grow as lithophytes on rocks or cliffs, and a very few grow conventionally in the soil. While they vary immensely, most have cylindrical hanging stems that drape down.
And what is the difference between a Rhipsalis and a Lepismium you may ask? This is the territory of the truly devoted and something I was unaware of myself until researching this article. The ovaries of the Rhipsalis flowers are round and the flowers are scentless. The plants show acrotonic branching. The ovaries of the Lepismium flowers are rectangular and they may be scented. The plants display mesotonic branching.
Having spent some time travelling throughout South America, I have seen many species growing in the wild. Where there is moisture, the trees are covered in various epiphytes, which form gardens in the sky. Rhipsalis and Lepismium plants are often visible high in the canopy, hanging from horizontal branches.
Areas where these plants are highly memorable, include the Rio de Janeiro Botanic Gardens where various species of Rhipsalis and Lepismium plants thickly coat many of the large trees, and the drive up to Tucuman in Northern Argentina where the road runs through rainforest containing trees covered in Rhipsalis plants.
While almost all cacti are naturally found only in the Americas, the great exception and ‘riddle’ is the genus Rhipsalis. Species in this genus are found in tropical Africa (Sierra Leone and Ethiopia southwards to Angola and eastern South Africa), Madagascar, Mauritius, the Comores, Mascarene and Seychelle Islands, Sri Lanka and the Indian subcontinent. Migratory birds are though to be responsible for this unusual distribution, which proves just how effective these plants are at distributing their seeds.
At one time Rhipsalis and Lepismium were the provenance of the collector. However in recent years I have been seeing more and more of them for sale – a great surprise. Visiting the Newtown Garden Centre in inner Sydney recently, I was astonished to see the size and variety of Rhipsalis and Lepismium plants on offer. In the inner city, hanging plants have become increasingly popular and Rhipsalis and Lepismium, due to their hardiness and novelty value, are particularly in demand.
You may also spot Rhipsalis and Lepismium plants on many of the green walls that are frequently seen in our cities. Take a closer look at some of the hanging plants next time you see one.
Rhipsalis and Lepimium have always been popular with older gardeners. They are hardy, shade tolerant, tolerate erratic watering and neglect. They are readily propagated and swapped or given away. Many gardeners have no idea what they are growing.
The texture of the stems and weeping character is the main attraction however many species have attractive flowers or berries in shades of white, cream pink and red.
If you get really interested in locating more of these plants, one of the best suppliers in Australia is Coachwood Nursery in NSW which sells a variety of named species and operates a stand at many garden events around the country.
My eyes were really opened to these plants when I visited the garden of Derek and Margaret Butcher in Adelaide. Derek and Margaret are best know for their work with bromeliads (‘Uncle Derek and Auntie Margaret’), however thy have also amassed a great collection of Rhipsalis and Lepismium plants over the many decades. Along with US grower Ken Friedman, Derek has developed a great introductory website to these plants. He has also spent years trying to identify the plants he grows. Like many plants, the flowers are the most useful aid in identification. Many species look identical until they flower. Conversely some plants look quite different from one another but may prove to be different forms of the same species.
There are many wonderful species to grow, and many are now widely available – however this will be the focus of another blog.
Rhipsalis and Lepismium are very tough and make great hanging basket plants, hung from trees or grown in bush houses. Most plants like a bright semi-shaded location, however some species will grow very well in full sun.
Being succulent, Rhipsalis and Lepismium are hardy and will tolerate dry periods and some neglect. However if plants are well watered and their nutritional needs met, they will grow very fast and look much more impressive.
Most species come from tropical and subtropical habitats and grow well in these climates, however I have seen excellent collections of these plants grown under cover in both Melbourne and Adelaide.
I grow some 60 species of these plants myself and maintain a labeled representative collection in hanging baskets, grown in standard potting media with a little additional fine gravel. The plants are fertilised with a controlled release fertiliser and hung from trees. These plants provide propagation material with which to experiment and use in other areas of the garden. Plants do well ‘poked’ into the side or bases of staghorn ferns (Platycerium species) or hanging baskets to provide a cascading addition to the composition. Some of the hardier species can also be attached to certain trees, and if well watered initially, can be left to grow as they do naturally in the wild. Some plants make great groundcovers over shaded banks or retaining walls. In the future I intend to use a few more species on experimental green roofs and green walls.
Mistletoe cacti can be used imaginatively to enhance our gardens, courtyards and verandahs. They can provide aerial interest, texture and colour. They have proved themselves to be tough and reliable performers. They certainly are becoming more popular, which does surprise me as they are not showy and do not have large colourful leaves or flowers. However they have a wonderful weeping habit, fine textural quality and an interesting character, which can contribute to a stunning garden as demonstrated by Brendan Moar last year.