The secret of the knights star
Hippeastrums, South American members of the Amaryllis family, are among the most flamboyant of all cultivated bulbs. Brian Mathew tells of their origins and of the hybrids they have spawned.
This article first appeared in the Spring '99 issue of Kew
In our excitement over the use of modern techniques such as genetic analysis to discover more about plant relationships it is tempting to talk of revolutionising botany, and of overthrowing the work of generations of botanists. But it would be almost impossible to interpret the results of genetic analysis without the classifications they devised.
Carolus Linnaeus (1707 - 1778) was the father of classification as we know it and, rather than be amazed that we have learnt rather a lot in 300 years, it is perhaps more amazing to realise how much he got right. Fundamentally, for example, he realised that in botany the reproductive structures - flowers - were the most stable organs on which to base his classification. They have remained the most useful characters for field botanists, even with the arrival of genetics, for you can't take a genetics lab into the rainforest with you. Linnaeus was also the first to apply the system of using two Latin names - and was a dab hand at using weird and wonderful plant characteristics to coin new Latin names for the plants he classified.
Take, for example, those most flamboyant flowering bulbs, the South American Hippeastrum. What have these extrovert plants to do with hippos, the Greek for a horse? They are members of the amaryllis family and look very much like the Cape belladonna lily of South Africa, Amaryllis belladonna. The horsey connection was first made by Linnaeus who named one of his South American species A. equestris. Exactly what was in his mind when he described this species we shall never know, but in Curtis's Botanical Magazine of 1795 is an explanation: describing the two parts of the spathe which encloses the buds, William Curtis commented that these 'standing up at a certain period of the plant's flowering like ears, give to the whole flower a fancied resemblance of a horse's head.'
Dean William Herbert, a nineteenth-century botanist and cleric, was a great authority on the amaryllis family and realised that, although superficially similar, these exotic Latin American plants were not very closely related to the Cape belladonna lily after all. So he separated them from the genus Amaryllis and coined a new name which maintained Linnaeus's equestrian connection, albeit in rather convoluted form which only chess players will instantly catch: 'I have named [them] Hippeastrum or Knights-star-lily, pursuing the idea which gave rise to the name Equestris.' But in spite of Herbert's efforts to distinguish the two, the name 'amaryllis' has stuck among gardeners as a general one for both old and new world plants.
Hippeastrums have a long history in cultivation, but not as long as that of their close Mexican relative, the St James's lily or Jacobean lily which arrived here in 1593. It was for a long time known as Amaryllis formosissima - 'the most beautiful'. More recently it was renamed Sprekelia but it is genetically so similar to the hippeastrums that it can be crossed with them. Its deep blood red petals, roughly arranged in the shape of a cross, were thought to resemble the emblem on the mantles of the Spanish Knights of St James, hence its common name - one infinitely preferable to that coined by John Parkinson - 'The Indian Daffodil with a red flower'!
It was not until the mid 1700s that two true Hippeastrum species were introduced to cultivation from South America: the scarlet-flowered H. reginae; and H. vittatum with its white-and-red-striped blooms. Not long after this that people began to realise how easy these plants were to hybridise, to create even more showy flowers. A 'certain Mr Johnson' from Prescot, loved amaryllids and crossed H. reginae and H. vittatum to produce an excellent vigorous hybrid with rather small but elegant bright red, white-striped flowers. Sadly, his greenhouse and its contents were accidentally destroyed but not before some bulbs of these very first hybrid hippeastrums were passed on to the Liverpool Botanic Garden, so it is still with us today and is known appropriately as H. x johnsonii.
From this early beginning the quest for 'improvement' began and a huge range of hybrids were raised, using the characteristics of various species but especially those that would impart a greater flower size to their offspring. Although at one time this may have been considered desirable, gardening taste has gone full circle and the tendency now is to return to the smaller-flowered species.
There remains an enormous potential for developing new hybrids from crossing the wild species. Apart from the gaudy reds and oranges of the sub-tropical, hummingbird-pollinated species, there are fragrant ones with long trumpet-shaped white flowers, almost certainly pollinated by moths, and dainty, small-flowered species from the Chilean Andes. Others have rich green and red stripes, some a netted pattern of veins and there is even a yellow-flowered one.
Just as variable are their habitats, ranging from the margins of sub-tropical forests and grasslands to mountain slopes with frost and snow in winter. These hardy species are gaining in popularity and can be grown outside in southern England.
Whatever their origins, be it wild species or complex hybrids, generations of botanists and gardeners have marvelled at the knights-star-lily, and Kew's early directors were particularly impressed. Sir William Hooker, when the green and red H. psittacinum eventually flowered, declared that 'my expectations of it have been fully realised and I think it may fairly be pronounced the most splendid individual of this splendid genus'. Some 30 years later Sir Joseph Hooker, not to be outdone by his father, on seeing the bizarre yellow, red-spotted A. pardina, observed, 'it is certainly the most striking species of the genus known to me, and even Mr Fitch's [the Kew artist] skill has failed to give full effect to the dazzling contrast of the bright vermilion spots on the translucent substance of the perianth.'
Hippeastrums have had a long connection with Kew and its environs. One of the greatest authorities on the family was John Gilbert Baker (1834 - 1920), a former Keeper of the Herbarium. Across the Thames in Isleworth, another local resident fell under their spell. He was Arthington Worsley, an extraordinarily talented man in many fields including collecting and growing amaryllids. One Brazilian species in particular held his fascination: 'No one who has ever climbed in the Sierra from Petropolis, and seen Hippeastrum procerum at home, can forget the amazing beauty of the scenery unmatched, probably in the world. If he does not then and there fall in love with the amaryllids, he should be provided with a new pair of eyes.' It is not just the mountain habitat of this very rare plant that is impressive, for Worsley's extraordinary amaryllis, now known as Worsleya procerum, is unique in its large blue flowers and evergreen fans of arching leaves. It has been grown at Kew, and has occasionally flowered, but it is an event that makes the blooming of the titan arum - last seen at Kew three years ago - seem frequent.
Another resident of the area was the inspiration behind Kew's first Hippeastrum Festival. Veronica Read is the enthusiastic National Collection holder of Hippeastrum for the NCCPG. The Collection now comprises 74 named cultivars and about 20 species. She collaborates with the nursery trade to build up the collection. Even varieties which have now been superceded in the trade are worth keeping since they may well constitute valuable breeding stock - yet could so easily succumb to the pressures of the market and be lost forever.
Most people are familiar with the huge hybrid hippeastrums which are sold as winter pot plants, but those on display at Kew will be a special selection chosen by Veronica Read to present some of the less well-known varieties and to show the new developments in hybridisation including the smaller, more elegant forms of today's breeders.
Brian Mathew was a botanist at Kew and is a former Editor of Curtis's Botanical Magazine.