Thomas Mehlhose, Horticulturist, Kershaw Gardens Nursery, Rockhampton Regional Council
Credit: T. Mehlhose
A BGANZ Professional Development Award report
I am the Nursery Team Leader at the Kershaw Gardens Nursery in Rockhampton, which supplies plants to the local parks, botanic gardens and street tree programs. It also provides local endemic seedlings to revegetation contractors, who are funded by various not-for-profit entities such as Fitzroy Basin Association and Capricornia Catchments.
In 2022 I was awarded a BGANZ Professional Development Award to shadow the nursery managers at the Australian Botanic Garden Mount Annan nursery and the National Herbarium of New South Wales. The goal was to return to our humble regional council nursery in central Queensland with some new skills and useful information.
My main focus was to help Rockhampton Regional Council (RRC) achieve the lofty goal of implementing a comprehensive database of botanical specimens within the Rockhampton Botanic Gardens and Kershaw Australian Native Gardens, beginning with the Kershaw Gardens Nursery. I was extremely fortunate to be granted access to the behind-the-scenes activities within the two facilities, and to learn firsthand from the gracious and knowledgeable industry experts within.
Here are some highlights from and reflections on my two-week visit in February 2023. The Australian Botanic Garden Mount Annan (ABGMA) holds the prestigious title of being Australia’s largest botanic garden, spanning over 1,000 acres south-west of Sydney. It boasts a collection of over 4,000 species and is also home to the National Herbarium of New South Wales and the Australian PlantBank. The Nation Herbarium of New South Wales is one of the largest herbariums in Australia and houses more than 1 million specimens, including several important historical specimens, such as 800 plant collections made by Joseph Banks and Daniel Solander during Cook’s expedition in 1770.
The Australian PlantBank is a state-of-the-art, award-winning facility and is a significant member of the Millenium Seed Bank Partnership, the largest ex situ plant conservation program in the world, coordinated by Kew Botanic Gardens. This international partnership extends across the globe, with over 2.4 billion seeds in storage collectively. Inside the PlantBank I was able to observe the science in action, from the tissue culture lab to the deep freezers. The seed storage facility was fascinating. Walking into the short-term storage cold room set at 4 °C was a real blast and quite invigorating. It was probably in my best interests that I wasn’t given the opportunity to step inside the long-term storage freezer set at –20 °C. Many rainforest species have seeds that are incalcitrant to freezing because of their high fat content, so are kept as tissue culture specimens and cryogenically frozen at –196 °C. I was not allowed near the cryo-chamber.
I witnessed several experiments, from light and temperature variation germination trials to using liquid nitrogen and a special machine to map and measure the energy volatility within a macadamia seed as it ruptures. It releases a spike of energy as it approaches freezing temperatures. Experiments such as these will help us better understand and improve long-term storage possibilities for these types of rainforest species in the future.
Back outside to where I was possibly less of a danger to myself, I was humbled yet again by the generous and knowledgeable people who work at this prestigious institution. I was given the opportunity to see first-hand how the nursery is managed and how the plant database dictates and aids the intersection between the scientific and the practical.
I also had the opportunity to assist the Botanical Records Team in the stocktake of one of the garden beds outside PlantBank using GPS markers. It takes a whole team of smart cookies to keep the botanical database up to date and accurate. The nursery at ABGMA not only provides beautiful native stock to the botanic gardens but also houses crucial experiments and propagation programs for rare and threatened species, run by the scientists and botanists working across the way at the Herbarium and the PlantBank. This is where the IrisBG database system really shines in keeping track of the genetic heritage, original collection details and the extensive notes on individual specimens, from propagation to the eventual GPS location of plant-out within the gardens or elsewhere. Each individual plant is assigned an accession number, linked to the database that will accompany it for life, and beyond. Grafting Grevillea and Hakea with the knowledgeable ABGMA Nursery crew. Hopefully, mine are still alive!
Read the rest of the article (and other great articles!) in the summer BGer magazine here: https://issuu.com/bganz/docs/bganz_mag_issue_63_summer_2024/41
