Botanic Gardens Trust, Sydney, Australia

Australian Botanic Garden

Rainforest seeds

Rainforest seed project - a project to save rainforest species, our most vulnerable resource

Seedbanking is a cost effective way of conserving vulnerable species outside of their natural habitat but not all species can survive the seedbanking procedure that requires seeds to be toleratant of desiccation. Of particular concern, is the probability that many hundreds of rainforest species have seeds that are sensitive to drying out (desiccation sensitive).

Desiccation sensitive species, including many rainforest species, cannot be stored using conventional seedbanking techniques, making ex situ conservation difficult. Seeds of plants from drier habitats are adapted to being dried out and can therefore be stored in seed banks at low temperatures for decades without losing viability. However, fleshy fruited species from wetter environments such as rainforests may not be able to be stored this way and must be grown immediately or need to be stored as tissue culture collections or cryogenically (at -196°C).

The Rainforest Seed Project at the Australian PlantBank contributes to the Global Strategy for Plant Conservation and conservation planning for threatened species. The Rainforest Seed Project is generously funded by the Arcadia Fund who are providing 50% of the project funding over a five year period from 2013 to 2017. Supporters helping to match the Arcadia funding include Tony Maxwell & Robyn Godlee, the Clayton family, Dr Jan Roberts and Mr Ken Roberts AM and Principal Conservation Partner HSBC.

We have almost secured our $600,000 fundraising goal for this project and invite you to join our generous donors and help us reach our target and ensure the success of this project. You can donate on line here or contact the Development team at the Trust on 02 9231 8366.

Key features of the project

The core objectives of the project are to:

  1. Understand how rainforest seeds germinate and grow
  2. Screen species to determine whether or not they can be stored by conventional seedbanking
  3. Work in close collaboration with local, national, and international scientists to help conserve rainforest plant species worldwide
  4. Store the seed if it tolerates drying, or conduct further research to identify the best alternate method of conservation (typically this would involve developing tissue culture and cryostorage techniques)

Significance of saving our rainforests

Rainforests perform a vital role in maintaining the health of the planet by balancing greenhouse gases through oxygen release and carbon sequestration, and releasing water vapour to fall as rain. They contain a vast amount of biodiversity, provide habitat for many animal species, and provide livelihoods for many indigenous people.

Rainforests under threat

An intergovernmental panel of 2500 leading world scientists predicts that at least one third of the world’s forested areas will be adversely affected by global warming. Rises in atmospheric temperatures of between 3° and 5°C are expected over the next 50 years and this will drive many species to extinction.

Rainforest species are often highly adapted to their habitats and are unable to adapt or move in response to these predicted changes. Global warming will increase the frequency and intensity of wildfires to which many rainforest species are poorly adapted. Unsustainable logging, urban and agricultural development into rainforest areas will further impact on rainforest viability.

Australian rainforests - diverse and vulnerable

Australian rainforests cover only 0.3% of the land and yet contain more than 50% of the plant biodiversity of our nation. Three significant World Heritage listed areas that occur on the east coast of Australia have large rainforest components. These are the Wet Tropics, the Gondwana Rainforests of Australia and the Tasmanian Wilderness. The ‘Gondwana Rainforests’ of Australia World Heritage Area, in north-east NSW and southern Queensland, is described as a ‘discontinuous chain of islands in a sea of fire prone eucalypt and agricultural lands’. It contains more than 200 species of rare and threatened plants and animals.

Outcomes of Rainforest Seed Project research

  1. A gene pool of Australian rainforest species will be created and maintained.
  2. Management of wild species will be improved as conservationists can access seed biology information through databases to make informed decisions.
  3. Germplasm will be available for further research on plant growth and the ability to withstand stresses like temperature extremes, salinity, disease and a myriad of factors that cannot be tested in wild populations, because of obvious threats to their continued survival.
  4. Seeds and other regenerative material will be available for reinforcing or replacing lost or vulnerable plants in the wild. This process, ‘translocation’, is a last ditch effort to maintain plants growing in their wild habitats, a radical step that has been used in many parts of the world. (Our aim is to ensure that species are managed so that translocation is not necessary, but sadly, fragile habitats and species are impacted by human activities. For example, there are only a few species of the food crop Macadamia and two of these are vulnerable and endangered. If we lose wild relatives, breeding and development of new plants will be severely impacted for the future).

History of the Rainforest Seed Project (2008-2012), previously funded by Allianz and private donors

Click here to view reports.

Further reading

  • Hamilton KN, Turner SR and Ashmore SE (2009) Cryopreservation. In Offord CA and Meagher PF. Plant Germplasm in Australia: strategies and guidelines for developing, managing and utilising ex situ collections. Australian Network for Plant Conservation Inc., Canberra. Available from the Australian Network for Plant Conservation.


Recent Publications


Rainforest fruits



Tree bark

Seed germinating
Our amazing rainforest fruits and seeds. Photos: K. Hamilton

Cryopreservation of seeds of rainforest fruit
Cryopreservation of seeds of rainforest fruit.
Photo: A. Biggs

Citrus garrawayi
Citrus garrawayi
Photo: K. Hamilton

Citrus garrawayi - fruit segment
Citrus garrawayi - fruit segment
Photo: K. Hamilton

Protrusions on seed coat of Citrus garrawayi
Protrusions on seed coat of Citrus garrawayi
Photo: K. Hamilton


Nightcap National