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Experimentation on a Large Scale – an Analysis of the Holdings and Resources of Botanic Gardens

Volume 3 Number 3 - December 1999
Peter S. Wyse Jackson

This paper presents some results of recent work undertaken by Botanic Gardens Conservation International (BGCI) to document the range of botanic gardens resources existing in the world including the results of a preliminary analysis on their living plant collections

When BGCI was created in 1987 a computer database was established listing every known botanic garden in the world, as well as to hold details of their resources, staff and activities. The aim of the database was to support the development and subsequently the implementation of the Botanic Gardens Conservation Strategy (WWF, IUCN and BGCS, 1989). An extensive survey of institutions maintaining living collections was undertaken and when an international directory of botanical gardens was prepared in 1990 it contained 1,400 institutions. This was a considerable increase from the 708 included in the previous edition in 1983.

Today the total of botanic gardens listed by BGCI has risen to 1,846 worldwide, in 148 countries.

It is worth briefly commenting on the cause of this rapid increase. Certainly, the lack of a very clear definition as to what constitutes a “botanic garden” has blurred the edges between what are public parks or private collections and what are true scientifically-based botanic gardens. Some institutions have been accepted into the list even though they might only be marginally described as a botanic garden. A 1963 definition of a botanic garden given by the International Association of Botanic Gardens (IABG) was “a botanic garden or arboretum is one open to the public and in which the plants are labelled”. However, the Botanic Gardens Conservation Strategy contains a more useful list of characteristics defining a botanic garden, including:

  • an underlying scientific basis for the collections;
  • proper documentation of the collections, including wild origin;
  • adequate labelling of the plants;
  • open to the public; and
  • undertaking scientific or technical research on plants in the collections.

However, there are many botanic gardens which are clearly “botanic” gardens but which do not meet one or more of these and other criteria. Our most recent definition is one that we hope encompasses the spirit of what is a true botanic garden.

“A botanic garden is an institution holding documented collections of living plants for the purposes of scientific research, conservation, display and education”
In some instances a garden has retained the name “botanic” for historic reasons. The plant collection may survive but all scientific activities have ceased and documentation has been lost. One might argue for the removal of these from the list. However, experience has shown that it is precisely these institutions in many parts of the world that are currently being revived, redeveloped and re-established to become potentially important botanical centres.

Nevertheless there are also a very large number of new botanic gardens being created in most parts of the world. BGCI learns of a new botanic garden project somewhere on average once a week. The majority of these new botanic gardens are in parts of the world where there are relatively few. Most are relatively poorly resourced but nevertheless most are aimed at contributing to the conservation and sustainable use of native plants. The fastest growing sector in the botanic garden world is the creation of community botanic gardens - gardens designed to serve specific needs in their local communities and often managed by those same communities. Examples include many new botanic gardens established in small towns throughout Australia, or others recently begun or proposed in Colombia and Brazil. In Vietnam, a number of new botanic gardens have been created alongside national parks, designed to play roles in integrated conservation, sustainable development and public education.

Before 1949 there were only three sizeable botanic gardens in China, and a small arboretum. By 1983, 21 further botanic gardens had been set up by the Chinese Academy of Sciences or at the provincial level. These were mainly for the purposes of plant introduction. Today there are more that 120 botanic gardens in China making contributions in scientific research, plant conservation, environmental education and public amenity and recreation roles.

It is clear to me that we are in a time when botanic gardens are being created at a rate never before seen. This is partly fuelled by greater plant conservation needs than ever before and by heightened public awareness of environmental protection - but also by the encouragement and support given by many botanic garden network organisations, including BGCI, that have grown over the last two decades.

 Table 1 Geographical distribution of botanic gardens and membership of BGCI

BGCI Members BGCI Members %
Africa & Ind. Ocean983738%
Central America  561629%
Former Soviet Union
Middle East 10770%
North America 297
South America
South east Asia
16 39%


About 60% of the world’s botanic gardens are situated in the temperate regions, in North America, Europe and the countries of the former Soviet Union (see Table 1). In the regions of the highest biodiversity, such as South America, South East Asia and Africa there are still relatively few. However, the steadily growing number of institutions in these regions gives us cause for optimism, particularly if ways can be found by the international community to build their capacity for scientific investigation and conservation and to support them technically and financially.

BGCI itself has grown steadily in the 12 years since its establishment so that it now includes over 500 member botanic gardens, in 110 countries, with good representation of most regions and major countries amongst its membership. We estimate that there are currently approximately 800 to 1,000 botanic gardens currently active in plant conservation. It is clearly from amongst these that BGCI draws and will continue to attract most of its members.

The range and variety of botanic gardens is enormous. They vary from institutions with five to six hundred people employed, to small botanic gardens managed by a handful of staff with a tiny budget, or even sometimes operated entirely by volunteers. This clearly impacts on their capacity for scientific research and conservation.

BGCI surveys conducted in the 1990s indicate that only 348 botanic gardens (of more that 1,000 surveyed) are known to have research staff (about 20%), although the total number of scientists known to be working in botanic gardens worldwide is an impressive total of well over 5,000 (5,350) (see Table 2).

Table 2 Recent BGCI survey of botanic gardens to show percentage of gardens with research staff (see text - nearest whole number)

 Out of:
348 gardens
 1846 gardens
52 botanic gardens
have over 20 research staff
45 botanic gardens
have 11 – 20 research staff
152 botanic gardens
have 3-10 research staff
99 botanic gardens
have 2 or less research staff
1,498 botanic gardens
have no research staff












In addition, 399 botanic gardens record that they have laboratories (22%) and a total of 428 botanic gardens record that they are allied to a research institute (23%) and or an herbarium. In the European Union alone, botanic gardens collections include 38 million herbarium specimens.

Clearly the capacity and resources of botanic gardens for research is considerable. However, their impact on science and conservation can be all the more effective if greater coordination and closer cooperation is fostered - and if agreed priorities are defined and articulated to become the basis of individual institution programmes. Documents such as the Botanic Gardens Conservation Strategy and its successor, the International Agenda for Botanic Gardens in Conservation (due for publication in June 2000), provide useful guidance for individual botanic gardens. Several national and regional network organisations, such as the AABGA and CPC in the U.S.A. have prepared very focused strategies to guide their members. In other regions, Action Plans for botanic gardens are being prepared, such as the Conservation Action Plan for Caribbean Island Botanic Gardens published in 1998 and an Action Plan for botanic gardens in the European Union, due for completion in 2000.

It is not difficult to document the whereabouts of each botanic garden and their staff and facilities, but obtaining a clear view of what collections they maintain is much less easy. In surveys, botanic gardens worldwide have indicated to us that together they cultivate more that 4 million living plant accessions, as well as maintaining a further 250,000 seed accessions in their seed banks. 152 botanic gardens have reported to BGCI that they have seed banks.

So far we can only make an estimate of the living plant holdings of botanic gardens – the current estimate is that approximately 80,000 species are in cultivation in one or more botanic gardens worldwide – almost 30% of the known world flora. While no one should argue that these collections are represent genetically diverse collections of the majority of these species, nevertheless they are a hugely important resource for science and conservation.

For example, recent work we have undertaken to document medicinal plant collections in botanic gardens has shown that there are 480 botanic gardens with medicinal plant collections, widely distributed around the world.

However, one should not write off all botanic garden collections for their genetic unrepresentativeness. For example, in the botanic gardens that are part of the Center for Plant Conservation’s network, considerable effort is put into assuring that their conservation collections are genetically representative of the whole species. And in a recent analysis of accessions maintained at Bogor Botanic Garden in Indonesia, I was astonished to find records of 496 separate accessions of a single species, the orchid Bulbophyllum anceps were being maintained in its collection. They had been gathered from all parts of Indonesia, in Kalimantan, Sumatra, Irian Jaya, Java, Sulawesi, Bali and other islands. This was by no means exceptional in the garden and there were over 150 accessions of another orchid Eria apporoides, 86 accessions of the rattan palm Calamus pseudomolis and 25 accessions of a single Dipterocarpus species (D. alatus).

The figure of 80,000 species in cultivation in botanic gardens has been derived from three different approaches:

1. The first approach has been to estimate the percentage of floras from each part of the world known to be in cultivation (some would say that this is a “guess” rather than an “estimate”!). When we combine the totals for each region of the world the figure amounts to over 80,000. Furthermore BGCI has conducted surveys on known rare and endangered species in the early 1990s and up to the present time which show that for particular regions a relatively high proportion of their endemic floras are represented in cultivation (see Table 3).

Table 3 BGCI surveys of rare and endangered species by region

Total no. of species surveyedTotal no. of species located in cultivation 
New Zealand
South Africa
Australia  1867893
Mascarene Islands












Overall, 35% of the total known rare and endangered species from these regions are represented in cultivation at least one botanic garden. If this proportion extended to the world flora then the total in cultivation would be approximately 80,000.

2. A second way to arrive at this total has been to estimate the percentage of key plant families that are in cultivation. For example, there may be many as 10,000 (of the 17,000 known) orchid species in cultivation. . BGCI surveys conducted (again on known rare and endangered species) have shown that for the following groups a relatively high proportion are in cultivation (see Table 4).

Table 4 BGCI surveys of rare and endangered species by family


Total no. of species

Total no. of species
located in cultivation
 Cycads 10581
 Conifers 264179
 Palms 665298
 Ferns 60073
 Orchids 986306









Overall, 43% of the total known rare and endangered members of these popular groups are known to be in cultivation. If this proportion was repeated for the whole flora then we would expect about 120,000 species to be represented in cultivation. However this is certainly not the case and the occurrence of many families in cultivation is at much lower percentages than many of these totals. For example, Barthlott and his collaborators (Botanishe Gärten und Biodiversität Bundesamt für Naturschutz, 1999) in Bonn Botanic Garden have recently suggested that only 5-10% of the 10,000 species of Rubiaceae are in cultivation but that over 90% of the Cactaceae are cultivated in gardens (see Table 5) .

Table 5 Estimates of representatives of different plant groups in botanic gardens (after Barthlott, et al., 1999).

No. of species No. in cultivation 
 Orchidaceae 30,000 >25%
 Asteraceae 25,000 <10%
 Rubiaceae 10,000 5 – 10%
 Eupohorbiaceae 8,000 5 – 10%
 Bromeliaceae 2,700 60 – 70%
 Cactaceae 1,000 >90%
 Didiereaceae 11 100%
 Temperate trees
 Tropical trees and shrubs
 Freshwater plants
 Epiphytes  >40 – 50%
 Succulents  >60 – 70%













3. A third way of estimating the number of species in cultivation in botanic gardens is to compare the actual totals or lists of species in cultivation in different botanic gardens and then see how many are unique to each collection. Barthlott et al., 1999 estimate that German botanic gardens alone cultivate as many as 50,000 species. At the Royal Botanic Gardens, Kew, U.K. almost 32,000 taxa are recorded in cultivation. Berlin Botanic Garden, Germany has 20,000, the Royal Botanic Garden, Edinburgh, U.K. 17,000, New York Botanic Garden, U.S.A. has 15,000 and the Indonesian Botanic Gardens (Kebun Raya Indonesia) approximately 15,000 taxa, St Petersburg, Russia 8,500, and so on.

In Germany a recent survey on the sum of 70,000 plant records in 10 botanic gardens revealed 27,000 taxa in cultivation in these gardens. BGCI is currently working to extend this work as part of a broader survey of botanic garden collections worldwide. Using a Red List prepared by the World Conservation Monitoring Centre (WCMC) in 1995 of rare, endangered and candidate species as the basis of its survey work, BGCI has located 10,000 species in cultivation of the 76,000 species listed by WCMC.

We have also recently begun work on the compilation of an electronic checklist of plants in cultivation, comparing the data from botanic gardens throughout the world. Comparison and enumeration of ten botanic gardens around the world gave a total of almost 50,000 species in cultivation.

The implementation of modern electronic data management capabilities has made it possible for the first time for us to determine accurately what species are in cultivation, where they are cultivated and to manage and gather other important details on each collection

The preparation and publication of the International Transfer Format for Botanic Gardens Plant Records (ITF) in 1987 provided a considerable impetus for many botanic gardens to develop standardized plant-recording systems. ITF helped many gardens to store data in such a way that it can be shared easily with others and stimulates close compatibility between different datasets throughout the world. ITF was also incorporated into most of the major botanic garden record system software packages that have become available, most notably BG-BASE and BGCI’s own software program, BG-RECORDER. In 1998 work was completed on a 2nd updated version of the ITF which has been made available by BGCI through the internet and is an accepted internationally agreed standard of the Taxonomic Databases Working Group. ITF2 has also been incorporated into the new version of BG-RECORDER, which is distributed free of charge to botanic garden members of BGCI worldwide. This program has been translated from English into Spanish, Russian and Bahasa Indonesia and has been of considerable assistance to many institutions that did not have the capacity to develop their own tailor-made systems.

Through electronic data management and exchange, we now have the opportunity to begin to document and coordinate the cultivated collections of the botanic gardens of the world so that they can start to function as a single but decentralized world collection available for research and conservation. In this way we can also seek to reduce the current duplication of effort whereby the same low priority species may be cultivated by dozens of botanic gardens, while at the same time rare species or critical plant populations are being lost in the wild.

Our analysis of the situation in botanic gardens suggests some future priorities.

A better standard of documentation of living collections is required by botanic gardens throughout the world, as well as resources to develop a global information system on botanical collections, probably largely via the Internet.

Botanic gardens in several parts of the world are urgently in need of financial and other forms of technical support and resources if they are to be able to play significant roles in scientific research and in conservation. I would particularly highlight the situation amongst the botanic gardens of the former Soviet Union where most botanical institutions have been devastated by the recent economic and political changes. There are still far too few well-supported botanic gardens in such countries as Brazil, Colombia, Indonesia, throughout Africa and much of Asia.

New training and study opportunities for scientists, horticulturists and botanic garden managers may help to address the situation to some extent and there is considerable potential for botanic gardens in Europe, North America and Australia to play an enhanced role in providing such opportunities.

Finally, it is clear that new resources are also needed to strengthen the networking organisations for botanic gardens throughout the world so that they too can provide the technical support, guidance and coordination that is so urgently needed.