Tasmanian Paleoendemic Plant Project

In 2024, the Inala Jurassic Garden (IJG) was awarded a grant from the Australian Garden History Society (AGHS) to expand and develop and ex-situ Paleoendemic Tasmanian plant collection as an IJG/AGHS collaboration at the IJG. Work was undertaken throughout 2025, and the main garden bed was finished (planted and mulched) in November 2025. Drainage problems were experienced in the area under the pergola designed to house more share tolerant species, and the problem is currently being addressed. We aim to finish this project by April 2026.  

Paleoendemic Tasmanian plants are Gondwanan relics; the term literally means ancient plants with a restricted distribution within Tasmania, comprised of lineages that have survived relatively unchanged for millions of years due to Tasmania’s relatively stable climate which is becoming more unstable, with increased fire risk and decreased rainfall. If these species are lost due to a catastrophic event like drought or fire, they are irreplaceable, hence the urgent need to conserve insurance populations in ex-situ collections.  

Propagating and creating ex-situ ‘insurance’ repositories are important to preserve them. Many species are difficult to grow in cultivation and are therefore rarely represented in gardens. The Inala Jurassic Garden (IJG) has succeeded in propagating many of these species from seed and cuttings using the expertise of Jonathan ‘Jonno” Esling and IJG manager Steven ‘Bori’ Morris. The aim of this project was to substantially increase these ex-situ insurance specimens in IJG by repurposing/enlarging/ creating 50x15m of garden beds and a 18mx5m walk-through pergola shade-house to increase the display area of these ancient plants for public access and education. 

Work started in April 2024 with the landscaping of the existing bed and adjacent grassy area near the western boundary of the IJG. A 20-tonne excavator and 10 tonne truck were used to prepare the garden bed, add more topsoil to improve drainage and add many dolerite rocks of all sizes to create a rocky, alpine landscape like that found in many of the species’ natural habitat. Sand was also added to improve drainage, and wood and dolerite stone were added as mulch for water retention and weed control. The pergola was built over the winter months and shade-cloth was added to the structure in November 2025. Specimens were propagated from cuttings and seed by Jonno and Bori and the main planting was carried out in November 2025, except two specimens of deciduous Fagus Nothofagus gunnii, which were planted in winter when they were dormant to reduce transplant stress. 
 
The project experienced an unanticipated problem in that the soil under the pergola became waterlogged after unusually wet and cold spring rains and concerns were raised because of the inadequate drainage issues for the plants. Fortunately planting of that area had not yet begun, as remedial work in the form of additional drainage is required before this area can be completed. This will involve digging a trench along the entire length of the tunnel and adding AG pipe (slotted drainage pipe) under the area to facilitate drainage into the nearby creek.  We are currently in the process of hiring a small machine to dig the trench and purchasing the additional materials required so that the project can be completed. This has also delayed completion of the adjacent smaller garden bed. We have the plants for those gardens in our onsite propagation house and anticipate these will be planted on schedule by April 2026; weed control and mulching will also be finalized in those areas by that time. An interpretive sign outlining the significance of the project and highlighting the collaboration between IJG and AGHS will be erected onsite  

AGHS criteria met during this project:  

IJG aligns with the AGHS mission statement to ‘promote awareness and conservation of significant gardens’ as a registered and accredited botanic garden that is open to the public with the primary aim of conservation and education. 

IJG also meets the criteria of a ‘Heritage Garden’ as defined by AGHS as ‘one we want to keep because of its aesthetic... scientific…value for…present, or future (heritage significance)’. IJG has demonstrated its scientific value in its collaboration with several top botanic gardens around the world and provision of non-replaceable specimens to several botanic gardens including the Australian National Botanic Garden (ANBG) Canberra, Royal Botanic Garden Sydney NSW (RBGS), Blue Mountains Botanic Garden Mt Tomah NSW, Mayfield Garden NSW, Royal Botanic Gardens Victoria (RBGV), Dandenong Ranges Botanic Garden VIC, Geelong Botanic Gardens VIC, Mount Lofty Botanic Garden SA and the Tasmanian Arboretum TAS. 

IJG also aligns with several AGHS objectives, including: 
‘To promote awareness and value of…an important component of Australia’s heritage’ (as described above),   

‘To undertake and promote research…through systemic identifying and recording (all IJG specimens are named and catalogued, with provenance data where known).  

‘To provide a forum for discussion and informed scholarly debate driven by research, concerning the identification and conservation of …rare old plants, the challenges of climate change…’ (research is a component of IJG practice and Tasmanian Paleoendemic species are rare, old and being affected by climate change).  

‘Administer and maintain a fund to target …professionals for the advancement of educational, scientific …. projects relevant to the Society aims, including sponsorships for participation in and contribution to the Society’s activities’- (this project is in line with the AGHS aims and IJG also advances  education and science by collaborating with rising stars in the horticulture industry such as  Evan Reid (Mayfield Garden, NSW ) and Harry Lush (The Gondwana Project). 

‘To exchange information and liaise with … organisations and individuals with similar aims and objectives for cooperative/collaborative ventures and active advocacy’- (IJG and AGHS are collaborating on this project). 

‘Contribution to conservation and best practice maintenance...through grants of approved works’ (IJG is listed as an accredited garden with Botanic Gardens Conservation International (BGCI) and ArbNet.   

Our heartfelt thanks go to the following for their invaluable contributions: 

• Jude Fakes, our Project Manager 

• Jonno and Bori for supplying good quality propagation material to maximise the success of the project. 

• Erhart and Ken for their expertise and care using large machinery and for supplying the dolerite rocks to complete the landscaping. 

• This project would not have been possible without funding from the AGHS, and we are proud to collaborate with them in this important conservation effort.