Alpine and Rock Garden team blog
The Alpine and Rock Garden team looks after a fantastic range of plants from the world’s mountain ranges. This blog includes stories about individual plants, growing techniques and trips to see alpine plants in the wild. You can visit plants from Kew's collection of alpines in the Davies Alpine House, the Rock Garden and Woodland Garden and read this blog to find out how the team gets to grips with cultivating them.
Acer palmatum ‘Sangokaku’, or the coral-barked maple, is a marvellous small tree for a woodland garden, with interest for every season. Here in the Woodland Garden, which surrounds the Temple of Aeolus at Kew, we have three specimens north of the Temple Mound. Right now they are awash with autumn colour – their small, deeply divided leaves range from butter yellow, through green and orange, to fiery red.
Autumn colour of Acer palmatum ‘Sangokaku’ (Image: Richard Wilford)
This year’s autumn colour is different from normal – a largely uniform buttery yellow, with almost no red or deep orange. I guess this is an indicator of the abnormally warm, dry weather we had during early October.
Acer palmatum ‘Sangokaku’, showing wonderful yellow hues (Image: Richard Wilford)
One of hundreds of named cultivars of the Japanese maple, the common name of "coral bark maple" celebrates the wonderful spring display. The young shoots and stems are bright coral-red, and before the leaves emerge the tree develops a pink halo. You can also see this bright red colouration on the petioles of the autumn leaves.
The leaves of Acer palmatum ‘Sangokaku’, showing their bright red petioles
The newly emerged leaves have a dainty pink flush, before becoming a vibrant lime green for the rest of the season, but it is in autumn that this wonderful tree steps into the limelight.
Acer palmatum ‘Sangokaku’
What more can I say? It’s perfect.
- Katie -
0 comments on 'The perfect Japanese maple?'
One of the autumn flowering Crocus species that I look forward to seeing each year is Crocus tournefortii. This species is not often grown outside because, unlike other Crocus species, it doesn't close its flowers at night or in inclement weather, so they are susceptible to damage, especially from rain. We first planted it out on the Rock Garden three years ago in a variety of locations and, as you can see, if given some protection by a neighbouring rock, the delicate flowers and amazing, many-branched styles are a wonderful sight. This is an entirely island species, from the Greek Archipelago, occurring in coastal scrub.
Crocus speciosus, or the ‘Showy Crocus’, is one of the easiest to grow, as it doesn’t mind sun or semi shade and will naturalise in grass and beneath shrubs. Like C. tournefortii, it has a much-branched, bright orange style in the centre of the flower, which contrasts brilliantly with the deep lilac-blue petals. Found from the Crimea, through the Caucusus to Turkey and Iran this species inhabits woodland, pasture and alpine grassland up to altitudes of over 2300m.
The first of what I consider to be next season's snowdrops is already up, but it is not as early as you might think. Galanthus reginae-olgae is a predominantly Greek species, discovered in the 1870s in the Taigetos Mountians of the Peloponnese, and usually flowers through October. They are a reminder of what is to come in a few months time, when the Galanthus elwesii begin to flower, the first ones appearing around Christmas time. Galanthus reginae-olgae is a reliable and beautiful species for a sunny warm spot. The flower stems extend and the flowers open before the leaves emerge, making it appear more delicate than perhaps it is.
Autumn-flowering Galanthus reginae-olgae
Last of the Roscoeas
As Galanthus regiane-olgae can be called the first of next season's snowdrops, then Roscoea purpurea ‘Red Gurkkha’ is one of the last of the roscoeas for this year. There are almost twenty species of these hardy members of the ginger family growing out on the Rock Garden, but most are not so late flowering; their peak blooming being between May and August. Not only does this form exhibit red colouration of the 'stem' or leaf bases, it is the only true red flowered form in this noteworthy genus. It was found in one location in Nepal in 1992, growing in open scrub, on a steep terraced slope, and was first exhibited by Kew at a Royal Horticultural Society show in London's Vincent Square in 1994.
Roscoea purpurea 'Red Gurkha'
Red hot pokers
The red hot pokers from the mountainous regions of South Africa are always exciting to see as we move into autumn. They hold forth upright, dramatic flowers, forming strong stout spikes which are topped by flowers of hot colours. Kniphofia caulescens comes from damp grassland in the Drakensberg Mountains in Lesotho and has been growing outside on the Rock Garden for three years, going through our last few cold winters without any trouble. I think it is helped by its sheltered position beneath a pine tree.
Left, Knifophia caulescens and right, Knifophia triangularis
I have a soft spot for Kniphofia triangularis as I remember it being one of the first plants I planted out on the Rock Garden when I came to Kew, ten years ago. It produces more flowers than K. caulescens and they also last a bit longer, well through October, and on a dull day they really make me smile as they are a burst of fire just before the days get noticeably shorter and more grey.
Red hot pokers on the Rock Garden
Moraea reticulata is a dramatic member of the Iris family (Iridaceae) and its route to the Rock Garden was via Kit Strange from the Alpine Nursery. She soon realised that it was too large and unruly for pot cultivation and so we decided to try it out on the Rock Garden. Here, in a south facing spot, it thrives and has more room to be admired. This species grows from a corm and has a very limited distribution in the wild, only being found in the mountains south of Queenstown in the Eastern Cape, South Africa. Plants are usually solitary and are found on steep grassy slopes, flowering in the wild in March to May (South African autumn). It is easily recognized by its channelled leaves and very characteristic cataphylls - a papery tunic that surrounds the corm and extends upwards well above the ground, forming a grey or brown fibrous network around the leaf and stem base. Moraea reticulata begins flowering in September here and has successive flowers right through October and sometimes into November.
Richard blogged about Cyclamen recently and whilst I was out taking photographs for this blog, I took these images of Cyclamen africanum and Cyclamen graecum, both flowering away whilst their tubers are quite exposed, well out of the soil. These species are often described as requiring protection from frost, but they have been happily growing and reliably flowering for several years out on the Rock Garden. We plant them in higher bays facing south or well drained cracks and crevices, where they thrive.
Left, Cyclamen africanum, and right, Cyclamen graecum, both flowering from exposed tubers!
Finally for now I should mention another South African plant that is looking good. On the Rock Garden the nerines are in full bloom, especially Nerine alta by the south door of the Davies Alpine House, and N. undulata, which can be seen further into the Rock Garden.
Left, Nerine alta, and right, Nerine undulata
These fantastic autumn flowers are just some of the highlights at this time of year so make sure to try and visit the Rock Garden in the next few weeks.
- Joanne -
4 comments on 'Autumn colour 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 -
0 comments on 'Autumn bulbs, inside and out'
In Armenia most people use the countryside as an extra larder. In many places, where farming is non-existent, people harvest mushrooms to sell by the side of the road to subsidise their income.
Collecting wild herbs (Image: Guy Moore)
They mainly sit by the one main-road, which goes through the whole of Armenia, and will sell the fresh mushrooms to people in passing cars and hungry lorry drivers. In the towns you can find little markets where people meet to sell and trade their herbs with each other.
Selling and trading wild and cultivated herbs and vegetables in an Armenian market
The plants they are selling are as diverse as the people selling them. You get all the usual vegetables, like radishes and onions, but soon you discover that there are more exotic herbs on the menu. Small tender shoots of polygonatum are for sale, in handy little bunches, which no-one who knows the plant in the UK would think of eating.
Mallow-like wild vegetable
Nice young leaves of a mallow-like plant were being sold, alongside large young shoots of Heracleum for pickling. Nothing it seems goes unnoticed in the countryside that might be of use. Allium paradoxum, which in this country is a pernicious weed, in Armenia they use extensively in cooking, thus controlling its rampant move across the countryside. Not a single herb which can be used medicinally is left untouched.
Left, Young shoots of Heracleum on sale, and right, Allium paradoxum
Thyme, for use as a tea, is also very popular and a complete mountain range has been named after it called the Urtz, which is situated in the middle of Armenia. Most of the herbs are cooked by first frying, and then adding to beaten egg, making a sort of vegetable scrambled egg. Other herbs are prepared with a salty brine, in which they are cured for a couple of months before being eaten as a compliment to meat and other vegetables. It seems that collecting herbs and vegetables in the hills is a family event; mum and daughter going out and collecting the herbs for their own use, and also teaching the new generation which ones are good to eat and what to do with them.
Wild medicinal herbs for sale
This is my last Armenian blog. The trip was sponsored by a travel scholarship from the Alpine Garden Society which sponsors several alpine related trips every year.
- Kit -
2 comments on 'Alpine travels in Armenia (part three)'
If you explore high enough altitudes in mountains such as the Alps and Pyrenees in July or August, you will reach elevations where summer has only just arrived. There you can find a range of alpine plants in bloom and meadows filled with colour. The following photograph was taken in the Caucasus Mountains of Georgia, in August, and shows a meadow above the treeline that was full of flowering plants, including Aquilegia, Campanula and the purple Geranium ibericum.
An alpine meadow in the Caucasus Mountains of Georgia
When you grow alpine plants at low altitudes they often flower earlier than they would in their high mountain home, but if you give them enough water and keep them cool, many will keep blooming right into summer. The genus Campanula, the bell-flowers, contains many small, compact mountain plants that flower in summer. Two examples in the Davies Alpine House are Campanula fragilis and C. elatines, both from Italy. Campanula elatines, from the Cottian Alps of north-west Italy, is grown in crumbly tufa rock in the Alpine House because it needs perfect drainage and can easily rot in winter if it gets too wet. This plant flowers right through the summer months.
Left, Campanula fragilis, and right, Campanula elatines
The only true summer-flowering Cyclamen is the European Cyclamen purpurascens. It comes from the Alps and further east into Slovakia and Hungary, and often grows in the dappled shade of woodland, in leafy soil among rocks. This species is found further north than other Cyclamen and is used to cooler summers and colder winters than other species, hence its summer growing season.
Cyclamen purpurascens in the Davies Alpine House
In Turkey, summers are generally hot and dry but growing in limestone crevices in the Taurus Mountains, at altitudes as high as 2,400 m, is Pelargonium endlicherianum. This genus is mainly South African and most species are not hardy, but the habitats of P. endlicherianum can be freezing in winter and this species is hardy enough to survive alpine house conditions, where it too flowers all summer long.
Left, flowers of Pelargonium endlicherianum, and right, two colour forms on display
The Himalayan Mountains, especially the south-facing slopes, are subjected to the summer monsoon, which travels from east to west, dousing the hills and valleys with sometimes huge volumes of water. When the rains arrive the plants get growing, and summer is the flowering season for many Himalayan plants, including lilies, roscoeas and Incarvillea. Planted in the Alpine House is the trailing Incarvillea arguta, with pink flowers on stems a metre or more in length.
Incarvillea arguta, from the Himalaya
If you are lucky you may see the wonderful flowers of Tigridia pavonia in the Davies Alpine House. Each large flower only lasts a day and is best in the morning. This plant species comes from Guatemala and Mexico, where it is dormant in the dry winter months. It grows and flowers in summer when the rains arrive. Like all the plants mentioned here, it is climate that determines flowering time, whether it is the warmth of summer reaching the high Alps, the monsoon advancing along the Himalayan ranges, or the wet season arriving in Central America. It means we can keep the Alpine House looking good all summer long.
Summer flowering Tigridia pavonia
- Richard -
2 comments on 'Summer in the Alpine House'
Keep up to date with events and news from Kew
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.
The Woodland Garden dons its winter coat: bonsai. by: Nafi
Autumn colour on the Rock Garden: It appears you planted Nerine alta outdoors. I just acquired some bulbs of this species and am wond ... by: Clayton
The winter flowering Cyclamen coum: Another informative blog. I find the photos intriguing and the cultivation tips very useful. I have ... by: Valerie
- newly discovered
- around the world
- of use
- ground breaking
- english garden
- garden plants