The world’s botanic gardens contain at least 30% of all known plant species, including 41% of all those classed as ‘threatened’, according to the most comprehensive analysis to date of diversity in ‘ex-situ’ collections: those plants conserved outside natural habitats.
The study, published in the journal Nature Plants, found that the global network of botanic gardens conserves living plants representing almost two-thirds of plant ‘genera’ (the classification above species) and over 90% of plant families.
However, researchers from the University of Cambridge discovered a significant imbalance between temperate and tropical regions. The vast majority of all plants species grown ex-situ are held in the northern hemisphere.
Consequently, some 60% of temperate plant species were represented in botanic gardens but only 25% of tropical species, despite the fact that the majority of plant species are tropical.