The “Frozen Garden” – Australia’s PlantBank

Plant biodiversity is one of the most important resources on planet earth. Food security, building materials, clothing and medicine all depend on diverse plant populations. Unfortunately, though, that diversity is being challenged in multiple ways, most notably from human exploitation, global climate change and natural disasters. In fact, researchers now estimate that some 60,000 to 100,000 plant species – that’s about one-quarter of all plants – are currently at risk for extinction. 

And that’s where Australia’s PlantBank comes in. 

Launched in 1986, the project was first called the New South Wales Seedbank, and its original mission was to collect seeds for the Australian Royal Botanic Gardens. Major renovations in 1999 and 2013 transformed the Seedbank into a center for research, teaching and the preservation of plant biodiversity, and now the PlantBank stores seeds from almost 5,000 species, half of which are from New South Wales. 

With 260 of the 611 threatened or endangered species in the region represented in the bank, the repository is well on its way to meeting one of the key goals of the Global Strategy for Plant Conservation: 75% of threatened plant species preserved in ex-situ collections by 2020. In 2003, the PlantBank began collaborating with the United Kingdom’s Millennium Seed Bank, and so has expanded its collection even more. 

The PlantBank preservation efforts depend on a team of dedicated plant biologists and engineers who are developing best practices for seed viability. Most seeds can be dried and kept viable at -20°C. However, some species require special treatment. For instance, plants that don’t produce many natural seeds, produce seeds that are vulnerable and short-lived or produce seeds that don’t tolerate desiccation before storage have to be banked with other methods. 

Fortunately, the PlantBank has the facilities and people to support even the most obscure seed types. Fleshy rainforest seeds, which don’t survive the drying process, are preserved in liquid nitrogen at -196°C. In addition, tissue cultures are also used to support the banking of species that don’t make seeds or seeds with special requirements, such as orchid seeds, which only germinate in the presence of a specific fungus. 

While preserving plant diversity may be its primary mission, the PlantBank is also dedicated to education. The facility is open to the public daily for tours and to watch scientists conducting research, and the staff leads workshops to train “citizen scientists” about the collection of scientific data. (There’s even a smartphone app that offers a “behind the scenes” look at current PlantBank projects!) 

In an interview earlier this year, John Siemon, the PlantBank’s project manager, said researchers have shifted their science “from behind our barbed wire fence” to places that are more accessible to the general public. 

It’s also worth noting that the PlantBank building was designed from the ground up to be a sustainable and efficient operation. The building itself has several unique sustainability features, such as a “thermal labyrinth” that captures cool air at night and uses it instead of air conditioning during the day and a rainwater collection system on the roof. 

Australia’s PlantBank is committed to preserving the rich plant diversity of the region. We’re affectionately nicknaming the bank the “Frozen Garden,” after the Frozen Zoo, which is dedicated to preserving animal diversity in Australia. Working together, these two biobanks are helping to preserve the planet’s fascinating and vital biodiversity long into the future.