Today large private orchid collections in the UK are but a distant memory, their demise coinciding with the advent of two world wars, and the immense changes in society they brought about.
The wild-collected orchids too – millions of them - have long since vanished. A legal trade in wild-collected specimens continued in the UK well into the 1970’s, and up until that time many orchid nurseries displayed benches of imported plants.
Today the importation of such plants is no longer permitted although, despite the ban, the illegal extraction and sale of orchids from their natural habitats continues around the world. Combined with continuing habitat destruction and a warming climate, the future for many orchid species in the wild looks bleak indeed.
And yet today most, if not all, orchids can be raised from seed comparatively easily. This was not always the case.
At first Victorian nurserymen were puzzled by these exotic blooms. The familiar powdery pollen had been replaced by clumps of pollen, and the sticky stigma was hidden beneath a novel structure in the centre of the flower – the column.
Successful pollination of these bizarre flowers was only one of their problems. Orchid seed is like dust.
A single capsule may contain thousands of minute propagules that, when the capsule splits, are dispersed on the merest breath of air.
But how to get the seed to germinate? In an attempt to mimic the orchids’ natural habitats, they tried everything they could think of: blocks of wood, pieces of tree-fern stems, cork strips, the moss that surfaced the pots of the growing plants ...
What they did discover was that seed of odontoglossum would only grow on the compost in which odontoglossum plants were growing, and that cattleya seed would only germinate on compost in which cattleya plants were growing.
Little did they realise at the time that, because the orchid seed was so minute it didn’t have a food reserve, that it needed a specific fungus to germinate in its natural habitat.
It wasn’t until 1899 that the need for such a ‘mycorrhizal’ fungus was recognised. Joseph Charlesworth pioneered this technique in his UK nursery, and began to grow thousands odontoglossums from seed.
The real game changer occurred in the 1920’s, however, when it was shown that most, mainly tropical, orchids could be grown from seed on a simple nutrient jelly medium. Indeed, today’s commercial orchid industry relies on the same basic technique, and millions of orchids are produced in laboratories around the world.
With around 30,000 species and counting (many new species are still being discovered every year), the Orchidaceae is second only to the daisy family in the number of species.
They are to be found on every continent apart from Antarctica. The majority are found in the tropics. Colombia for example has in excess of 4,270 species, Britain around 50.
Orchid growers in the early 19th century initially suffered from a lack of information about the natural habitat of orchids growing in the tropics.
Their initial assumption was that they all required warm, humid conditions, and accordingly grew them in hot and steamy stove houses. It should come as no surprise that vast numbers of imported plants died.
Odontoglossum crispum, for example, originates in the cool, misty cloud forests of the South American Andes. The growers were on a steep learning curve, but as their understanding of the requirements of individual species improved, so did their success in keeping plants alive.
Besides selecting the ‘best’ varieties of imported plants (and often consigning the remainder to the compost heap) the early horticulturists by and large couldn’t resist the temptation to try and ‘improve’ on nature, by cross-pollinating especially attractive plants.
Orchids are unusually promiscuous plants, and not only is it often possible to obtain hybrids between different species in the same genus, but often between plants in different, related, genera. Today many attractive and easy to grow plants are so-called intergenerics and are sold as ‘cambrias’. Large numbers of identical plants of the best varieties are produced by tissue culture.
Once confined to greenhouses, especially with the advent of central heating, it is now possible to grow a wide variety of different orchids at home and on the windowsill.
It is difficult to believe that in the 1970’s the now ubiquitous phalaenopsis (moth orchids) were regarded as being strictly plants for the hothouse.