What is a botanic garden? It is easy enough to describe botanic gardens as collections of living and preserved plant specimens, but the easy description largely misses the point – what are the collections for?
I’ve been fortunate enough to attend the Global Botanic Gardens Congress in Wuhan in China over the past week, and the role and future of botanic gardens was very much in focus. The Congress is held every three years and provides an opportunity for botanic gardens to share current research, policy and programs. The diversity of participants reflects the diversity of botanic gardens around the world. There is the Eden Project in Cornwall, where the key focus is on breaking down the barriers between people, plants and environmental action (in the process becoming the most visited fee-for-entry cultural attraction in Britain); there is the South African botanic gardens that are a key element of the National Biodiversity Institute in leading biodiversity conservation linked with poverty alleviation through innovative, community-based on-ground actions; there are such places as the Yves Rocher botanic garden that sifts new plants for application in Yves Rocher’s cosmetics range.
China’s botanic garden network has a clear focus on economic plants with a strong focus on urban landscaping and ornamentals, novel fruits and vegetables, forestry soil conservation, industrial energy and medicinal plant collections for development and assessment. For example, the Wuhan Botanic Garden has a 4 ha living collection of Actinidia [Kiwi-fruit] species and cultivars that is changing the nature of the Kiwi-fruit market internationally. Prof Huang Hongwen, the director of Wuhan Botanics and Congresshost on behalf of the Chinese Academy of Sciences, argue scogently for the broad social value of the intellectual capital that botanic gardens bring to plant collection, cultivation and assessment. Clearly this argument has been a powerful one in China, if not in the West.
Historically, botanic gardens have changed the world. The first European botanic gardens were literally pharmacies associated with medical schools in universities. Indeed. at Montpellier in France the botanic gardens remains within the Faculty of Medicine. The achievement of early botanic gardens was to help organise these living pharmacies into the science of pharmacology. Later botanic gardens played a significant role in developing and promoting new systems of plant classification that fundamentally changed our relationship with the natural world – so a botanical treatise in Chinese still uses botanical Latin binomials (such as Gingko biloba or Metasequoia glyptostroboides). There is of course much more to the classification system than this, but at least botanists around the world can match the captions with the illustrations!
Perhaps the most profound impact of botanic gardens has been in the service of empires. The great nations of Europe exploited the plant genetic resources and labour of colonised nations, or of other nations. The theft of rubber from Brazil, its establishment in the Ceylonese botanic gardens, and the subsequent establishment of rubber plantations in Malaya provides a glimpse of the role of botanic gardens during the Age of Empire.
The existence of the Museum of Economic Botany in Adelaide Botanic Gardens is an example of this theme: the Museum’s role was to exhort colonists to exploit the botanical resources of the world to ensure their own success, along with that of the South Australian colony and Great Britain. More recently, botanic gardens have played a major role in the greatest diaspora of plants the world has ever seen, as much for ornamental purposes as for economic.
A contemporary role for botanic gardens is in reconciling plants, people and environment. At the Botanic Gardens of Adelaide, we have programs that focus on such things as sustainable urban landscapes (including the still-new SA Water Mediterranean Garden), plant conservation (including the Millenium Seed Bank) and landscape restoration. I’ll have more to say about these initiatives later.
Apart from our scientific work, our management of the Gardens themselves remains the key to us attracting 1.5 million visitors each year. The challenge for the Gardens remains in connecting visitors with the significance of the Gardens’ role as a cultural and scientific institution while protecting the peace and tranquillity that many visitors seek – a balancing act that the Gardens have managed pretty effectively for the past 150 years.
Ginkgo Biloba (Maidenhair tree) & Metasequoia gylptostroboides (Dawn Redwood)
As I have been in China, let’s look at Chinese plants. The Chinese flora might be the richest on Earth – Magnolia, Rhododendron & Paeonia species are only a few of the long list of spectacular garden plants with centres of diversity in China. Ginkgo biloba and Metasequoia glyptostroboides illustrate how rewarding the flora of China is for botanists and gardeners. Both are trees of great botanical significance representing ancient lineages better known from fossils than from the contemporary flora, both are deciduous conifers and both are exceedingly rare in the wild. There is a suggestion that even the reputedly wild population of Gingko has reestablished from cultivated plants – indeed, the largest Ginkgo trees are all in cultivation, often associated with temples. Metasequoia was only discovered in the wild in 1941 – a similar story to the Wollemi pine. A cultivated specimen of Gingko in Lijiawan, Guizhou, China is 40m tall with a trunk diameter of close to 5m.
Ginkgo and Metasequoia reach modest proportions in both the Adelaide and Mount Lofty Botanic Gardens. Both are hardy, have attractive foliage with yellow to golden Autumn colour and few faults – although the female tree of Ginkgo produces a fruit that has been (with considerable prejudice) been described as putrid. Those who feel this way can obtain male clones fairly easily. Of the two, Ginkgo is a better choice on the Plains where its informal tendency isn’t profoundly impacted by lack of water – even a struggling specimen can be a valuable addition to the garden for the foliage alone. The more formal Metasequoia is probably best left in the Hills under current restrictions (or even in a large container on the Plains providing it doesn’t dry out).
Originally published in The Adelaide Review on 27 April 2007.