In their Mediterranean home, many bulbs burst into flower when the autumn rains arrive. At Kew you can see them on display inside the Davies Alpine House and outside on the Rock Garden.
A bulb is an adaptation to survive long periods of drought. Tubers, corms and rhizomes perform a similar function, storing water and nutrients underground, and waiting for the drought to break so they can grow and flower. Seasonal droughts are typical of the Mediterranean regions of southern Europe and North Africa, as well as parts of California, Chile, South Africa and SW Australia. In the garden these autumn bulbs, corms and tubers provide a boost to the flowering season late in the year.
Cyclamen graecum on the Rock Garden
Cyclamen can be seen in many parts of Kew, the most common being Cyclamen hederifolium, but on the Rock Garden you can find the less hardy C. greacum, which comes from Greece and Turkey. It does well in a sunny, south-facing position, where it can make the most of the autumn sunshine. Even less hardy, but still surviving outside in the most sheltered spots at Kew, is the North African C. africanum. For another African species you will have to go inside the Davies Alpine House, where you will see several pots of C. rohlfsianum, a species endemic to northern Libya and not hardy enough to grow in the open.
Left, Cyclamen africanum on the Rock Garden, and right, C. rohlfsianum in the Alpine House
Back outside on the Rock Garden, look out for the fantastic magenta-pink flowers of the South African Gladiolus carmineus. This plant comes from Western Cape in South Africa, an area that has a Mediterranean-type climate and is home to a huge range of bulbous plants in the Cape Floral Kingdom, one of the World's biodiversity hotspots.
South African Gladiolus carmineus on the Rock Garden
Also from South Africa is the genus Nerine. These bulbs are mostly just emerging outside at Kew but in the shelter of the Alpine House, the delicate blooms of Nerine filamentosa are open. This species differs from the other plants mentioned here because it is a summer grower, appearing in the summer rainfall region of Eastern Cape, although the flowers bloom at the end of its growing season, in autumn. In a couple of weeks the more robust Nerine bowdenii will be flowering outside in the gardens.
Nerine filamentosa flowering in the Davies Alpine House
Another plant that is flowering earlier inside the Alpine House than outside on the Rock Garden is Sternbergia lutea. On the Rock Garden, the blooms of this Mediterranean bulb are just opening but in the Alpine House they have been open for a couple of weeks. The impressive, bright-yellow, goblet-shaped flowers emerging from their large terracotta pots, make a real impact on the glasshouse benches.
Sternbergia lutea in the Davies Alpine House
There are plenty more bulbs on the way. Over the next few weeks the autumn flowering species of Crocus will be blooming inside and out, brightly coloured Oxalis will appear, and in a couple of months the giant squill, Scilla madeirensis will make a dramatic return to the Alpine House.
- Richard -
Several people contribute to the Alpine and Rock Garden Team blog. Richard Wilford is the Collections Manager in the Hardy Display Section at Kew. His responsibilities include all the areas where alpines are grown at Kew Gardens. The three team leaders, Joanne Everson, Graham Walters and Katie Price, each have their own particular parts of the Gardens to look after. Between them, these four experts have over 55 years experience of growing alpines.
Alpines at Kew Gardens are not only grown to create colourful and informative displays, they also play an important role in the research Kew carries out around plant naming, classification, biodiversity and conservation.
Mountains are found on every continent and each range has its own unique alpine flora, but these plants are under threat from climate change. As temperatures rise, alpines are forced higher and will eventually have nowhere to go. The alpine collections at Kew are studied to help us all understand the mountain flora better and make informed decisions about protecting its future.
"Probably the most beautiful glasshouse in the world is the Davies Alpine House at the Royal Botanic Gardens Kew", John Hoyland, Gardens Illustrated, April 2011
Richard Wilford has written a book on alpines, 'Alpines from Mountain to Garden', published by Kew Publishing. You can buy it in the Kew shops or from Kewbooks.com.
- newly discovered
- around the world
- of use
- ground breaking
- english garden
- garden plants
- english heritage
Keep up to date with events and news from Kew