7th Global Botanic Gardens Congress

Melbourne, September 25-29, 2022

26 October, 2022

Report: Chris Olney

When I accepted Pippa Moodie’s offer to attend the 7th Global Botanic Gardens Congress in Melbourne, I had no idea of its scale. I was more concerned that it was on at the same time as the AFL grand final ensuring premium prices for flights and accommodation.

I feel privileged to have had the opportunity to attend this stimulating world-class conference as a delegate among 500 people from 36 countries. I want to sincerely thank the Friends for the Tom Alford Scholarship which made it possible and affordable.

The three-day congress was held at the impressive Melbourne Convention Centre. There were 10 plenary sessions, 83 presentations and nine workshops. Needless to say, I didn’t get to them all.

The congress theme Influence and Action, Botanic Gardens as Agents of Change reinforced the critical role botanic gardens play to secure plant diversity for the well-being of people and the planet.

The increasing sophistication of plant conservation practices means botanic gardens are the agents of change for biodiversity conservation and restoration.

While many presentations painted a gloomy picture of the ravages of climate change on our environment, I came away feeling that we are in good hands. There are many plant people across to world – scientists, horticulturalists and volunteers – who have our backs and are keen to make a difference.

Botanic gardens hold 30% of the world’s plant species and have a key role in managing the biodiversity crisis and climate change. Botanic gardens are the main mechanism for people to learn about and understand the importance of biodiversity.

While everyone is wanting to plant trees to earn carbon credits, it is important to plant the right trees. Large scale tree planting is a major threat to biodiversity.  Work is being done on developing a system of biodiversity credits.

Keynote speaker Professor Michelle Leishmann from Macquarie University, Sydney opened the congress with lots of frightening figures illustrating the decline in plant species and grasslands across the world.

She highlighted the challenge facing urban forests, our street trees.  Just 30 species make up 53% of Sydney’s urban forest. In 40C heat last summer many species suffered and some died. However, there is no point in replanting the same type of trees. There needs to be increased diversity with an emphasis on tolerance to low water, high temperatures and pathogens. The development of climate ready seedlings is a priority.

As well as our impressive Kings Park presenters David Merritt, Laura Skates, Amanda Shade, Chelsea Payne and Emma Dalziell – plus a cameo role by Kings Park horticultural trainee Danni Hamilton who was invited to join the closing panel with Costa Georgiadis from Gardening Australia – I heard speakers from Colombia, India, South Africa, the US, the Caribbean, Britain, Cameroon, New Zealand, Spain and South America.


  • A special botany high school has been opened in Miami, US with 400 students; its first alumni are about to graduate from college and look for jobs; many students are from disadvantaged backgrounds. The course includes a day a week at the botanic garden.
  • Estaban Manrique from Madrid Botanic Garden, which was founded 267 years ago, said the garden had never experienced such climate devastation as it had in the last few years. Ancient trees were dying from the changing climate – very high temperatures in summer then snow for the first time last winter and now eight months of drought. Air pollution and a butterfly pest introduced from South America were also causing havoc.
  • Professor Terry Hartig from Uppsala University in Sweden conducted research as to why people go to botanic gardens. He found nature supports and promotes health and that people go to a botanic garden because it is a beautiful, natural place to get away from the demands and stresses of everyday life, not specifically for the plants. He calls it plant blindness.
  • Kurt Dreisilker from the Morton Arboretum, Illinois, US spoke about efforts to restore the region’s oak savannah. I had thought the burning regime of the Australian First Nations people was unique. However, Native Americans also regularly burnt vast tracts for hunting. Now the land is no longer burnt regularly the fire tolerant oak trees are being crowded by fire intolerant sugar maples. Work is being done with regular burning and thinning trees to restore the savannah and its important understory of plants.
  • Professor Ying Wang from South China Botanic Gardens, was the only delegate from China. The botanic garden at Wuhan is 300ha, with an arboretum of 1000ha and 200 scientists of which 43% are women. Covid has accelerated the transformation to the digital world and there has also been a huge increase in people visiting the gardens, with a record number in 2021. The gardens have 480 volunteers, 90% of them women. They are involved in plant painting, workshops on how to identify plants, plant jewellery, night garden and glow worm tours. The park has digitised plants blooming with time lapse, which is available online and very popular. More than 9 million people watched a virtual tree planting video posted online.
  • Other sessions highlighted the increase in pests and invasive species with the changing climate and increased mobility of goods and people around the world. The emphasis is on the need to educate people about the potential some plants have of becoming invasive weeds when they are not native to the environment.

I took part in two pre-conference tours. On Sunday, fittingly after Geelong’s grand final win, I went to the Geelong Botanic Garden, opened in 1867, which has a traditional old garden and new Australian area.

The tour included a walk at Anglesea heath and we looked at the site of a proposal to develop an Eden Project in an old Alcoa coal mine near Anglesea. The mine serviced a smelter until 2015. However, the Eden team is reluctant to commit to the project until the mine has been filled with water – a big problem to source enough water.

On Monday I joined a Melbourne walking tour looking at several ‘green’ lanes and plant walls plus a rooftop garden on a carpark which produces food for charity.

Dr Claire Farrell of Melbourne University explained the experimental Woody Meadow established near the Yarra. It involves mass planting of tube stock of a wide diversity of natives which are then coppiced to about 30cm every year. ‘Coppicing is our fire,’ she said. ‘But we have to put a sign up explaining what we are doing otherwise people complain.’

The congress was an inspiring, informative event with a congenial, friendly and positive atmosphere. The next congress is in Singapore in 2024.