Princess of Wales Conservatory
History and design
The Princess of Wales Conservatory was commissioned in 1982 to replace a group of 26 smaller buildings that were falling into disrepair. It was named after Princess Augusta, who was instrumental in founding the botanic gardens at Kew, and was opened in 1987 by Diana, Princess of Wales. It is the most complex conservatory at Kew, containing ten computer-controlled climatic zones under one roof.
The two main climate zones are the ‘dry tropics’, representing the world’s warm, arid areas, and the ‘wet tropics’, housing moisture loving plants from ecosystems such as rainforests and mangrove swamps. The eight remaining microclimates include a seasonally dry zone containing desert and savanna plants, plus sections for carnivorous plants, ferns and orchids.
Whereas the Palm and Temperate Houses make grand statements with their designs, the low-lying, angular ‘glazed hill’ of the Princess of Wales house is less obtrusive. The conservatory was designed by architect Gordon Wilson to be energy-efficient and easy to maintain and was built partly underground.
The southern end is heated more by the sun than the northern end, so this is where visitors find towering spikes of echiums and silver agaves from dry tropical regions such as the arid Canary Islands. The central area contains an elevated aquaria, complete with waterlily pond and the dangling roots of mangroves, plus displays of orchids and carnivorous plants. At the northern end are species from the moist tropics, including banana, pineapple, pepper and ginger.
There is also a ‘time-capsule’ buried at the southern end of the conservatory. Sir David Attenborough placed it in the foundations there in 1985 as part of the World Wildlife Fund’s Plants Campaign. Containing seeds of basic food crops and endangered species, it is not due to be exhumed until 2085. By this time, many of the plants it contains may have become rare or extinct.
Things to look out for
The pond within the aquaria section contains the Asian form of the giant waterlily Euryale ferox. This plant has huge leaves that can span two metres and are strong enough to take the weight of baby without sinking. On the lower level, there are viewing windows so visitors can see the pond from a fish’s eye view. Close by are separate tanks containing a rhombeus piranha, poison-dart tree frogs and baby water dragons. These displays demonstrate how plants and animals interact in their natural tropical rainforest habitats.
Towards the northern end of the glasshouse, are some familiar houseplants originating from the wet tropics. These include the African violet (Saintpaulia) and Swiss cheese plant (Monstera deliciosa).
There are about nine water dragons that live and breed freely in Zone 1. They provide a natural means of controlling unwanted insects in the Princess of Wales Conservatory but tend to keep out of sight of visitors.
Annual orchid festival
Once a year, the Princess of Wales glasshouse hosts a festival celebrating the beauty of tropical orchids. Kew’s orchid collection numbers some 1,500 species, and staff working its micropropagation laboratory are becoming adept at bringing rare species back from the brink of extinction.
Keeping the Princess of Wales Conservatory’s plants in good shape requires much hard graft behind the scenes. The team clean out the pools in spring, develop outdoor displays such as the Mediterranean Garden in summer, top up the glasshouse’s soil and replant beds in autumn, and prune plants throughout the winter.
There are sensors located on the glasshouse walls and secreted about the beds to feed environmental information back to the conservatory’s central computer. This switches on heat flows, opens vents to allow in cool air or prompts mist sprays to operate, until the preset conditions required for each climatic zone are met.