The Mornington Peninsula is renowned for its award-winning cool climate wines. But nestled among the grapes is another fruit that’s turning heads for its taste … avocados. Thanks to a groundwater discovery and assistance from us, grower Steve Marshall feels like he’s struck gold.
Steve Marshall is an agricultural scientist by training and the founder of Peninsula Avocados – a collective of three main growers who grow and market fruit from Mornington Peninsula. They currently crop around 30 acres of land in the region with avocados.
He’s been growing Hass avocados on the Peninsula for 30 years. While not the first to do so, he is the first to scale production and put the region on the map for commercial quantities of top quality green and gold fruit.
Steve says people typically associate avocados with warmer climes, but you can taste the difference in his cool-climate fruit.
“Similar to wine, avocados benefit from a long, slow ripening period the same way grapes do,” he said.
“Avocados from Queensland might grow quickly, but the longer hang time our fruit gets allows them to develop richer, nutty flavours and a smoother texture,” he said.
Steve said run-off dams provide most of their water. However, on one particular property this water had to be shared for other productive uses until he found a solution that would free up the high-quality dam run-off water just for the avocados.
“Avocados are very sensitive to salt and need good quality water to be able to thrive. Unfortunately, we can’t source from creeks or rivers because surface water is fully allocated in our area,” he said.
“The only option was groundwater. We’d drilled two shallow bores on the Main Ridge property years ago that were too saline,” he said.
Salinity in water is measured by passing an electric current between the two electrodes of a salinity meter in a sample of water. Salinity is typically expressed as electrical conductivity or parts per million. Avocado plants need water that has less than 300 parts per million of Total Dissolved Salt (TDS).
“I always wanted to investigate possible deeper aquifers, so I applied for the necessary bore and groundwater licences to get things going,” he said.
Steve said Southern Rural Water field officer Frank Crameri provided essential help that enabled the project run smoothly from day one.
“Frank’s advice about the restrictions around the placement of the new bore in regard to neighbouring bores was invaluable,” he said.
“I spoke to Frank numerous times, and he walked me through the licensing process. His knowledge and great service meant the process was straightforward and resulted in being granted a license quickly,” he said.
Steve was granted a groundwater licence on 5 July 2023, and brought in a drill crew that bored to 180 meters and hit a reserve that yielded water with a flow rate of 3.3 litres a second and 650 parts per million Total Dissolved Salt.
“It was a fantastic result because this water could be used in other areas of the Main Ridge property and we could reserve the high-quality dam water just for the avocados,” he said.
“In drought years, the new groundwater can be mixed with the dam water to provide extra water for the avocados if we take care to monitor the salinity,” he said.