Botanic gardens around the world are struggling to find the space to conserve rare plants and save endangered species. “They can’t all fit,” said Brockington. Cambridge University Botanic Garden, for example, is home to more than 8,000 species. “That’s more than a tropical country like Vietnam, growing in a tiny little acreage of Cambridge.”…Threatened plants must compete for space in botanic gardens with beautiful, famous – but less endangered – flowers, trees and landscapes that will attract visitors and inspire people to learn about gardening and the natural world….The first botanic gardens were founded during the colonial era, and almost all are located in the west. In the past, botanists from these gardens would engage in “extractive, colonial-type practices”, visiting poorer nations to “pull out whatever plants they or their rich patrons were interested in, bring them back and cultivate them,” Brockington said.

In 1993, a United Nations Convention on Biological Diversity attempted to stop this by assigning sovereignty over biodiversity to national governments, enabling states to “own” the genetic material within their geopolitical boundaries…But this is hampering efforts of gardens to collect endangered plants in the wild, and exchange seeds and plant material to protect threatened species from extinction. To maintain diversity and preserve the world’s living collections, plants must be regularly replaced or propagated. But since the convention was introduced in 1993, the number of plants in botanic gardens collected from the wild has halved.

“Political boundaries do not help us share material and collectively steward the world’s most threatened biodiversity,” Brockington said. Brexit, for example, has been “catastrophic” for exchanges of plant material between European botanic gardens, he said. “The bureaucracy of seed exchange can be so costly now, it would be cheaper for our staff to personally fly to somewhere like Sweden, with a legal amount of seed, than send it by post.”…Brockington wants the world’s botanic gardens to collaborate to safeguard plant populations by creating one big “meta collection”, where individual specimens of an endangered wild species are extensively cultivated in multiple institutions.

Excepts from  Donna Ferguson, The risk of extinction is accelerating’: world’s botanic gardens raise alarm with space to protect endangered plants running out, Guardian, Jan. 25, 2025