A three-year program to help growers mitigate against the impact of frost has provided new tools, strategies and support networks to help minimise risk and lessen damage caused by the unpredictable and sometimes catastrophic natural event.
The GRDC investment to inform grower decision-making around frost, managed by Mallee Sustainable Farming (MSF), draws on the expertise of agronomists to help with identification of frost and talk through decisions before and after a frost event occurs.
Starting with frost response workshops, the project evolved to develop a central digital resource and a range of mitigation strategies. This was driven by growers seeking a more hands-on role to help combat frost, says MSF program manager Tanja Morgan, who had oversight of the investment.
“We know that we’re never going to get rid of frost … but we’re focused on strategies and agronomic practices to help reduce either the severity or probability of frost occurring primarily at the critical flowering stage,” she says.
Digital resource
The MSF region covers some four million hectares across South Australia, Victoria and New South Wales, so to ensure the investment was relevant to the southern region, it partnered with four additional farming systems groups: Agricultural Innovation & Research Eyre Peninsula (AIR EP), Upper North Farming Systems, Birchip Cropping Group and Southern Farming Systems Group, with each group tailoring projects specific to their members’ needs.
Meanwhile, to counter the tyranny of distance, MSF itself turned digital, creating the Better Frost Decisions Facebook group that provides growers with resources to identify frost damage, assess options for frosted crops and plan for seasons ahead.
Updated regularly once frost events are looming, the page hosts live reports from agronomists in real time in the wake of frost events and features useful videos and information on how to best mitigate against frost and what to do should a frost occur.
Major frost response
Frost response materials have also been prepared and ready to be deployed in the event of a major frost, Ms Morgan says. This digital suite of “micro-learning” materials will be available in real time and includes fact sheets and training on what to look for and do in the days after a frost. It will also feature live broadcasts from agronomists, and growers will be invited to share photographs and their experiences while being provided with both professional and emotional support.
“A frost event can be emotional – it can be very traumatic to lose all your income in one cold night,” Ms Morgan says. “So rather than just holding a workshop and walking away, we’re providing bite-size pieces of frost response information, walking people through the process of what they can do while also providing them with some mental health support in that space.”
More than just conveying information, the Facebook page and resource package will help maintain community and support networks as people face the complex decisions that need to be made around frost mitigation and management.
“We’re trying to come up with innovative ways of making growers feel connected and part of the community,” she says. The Facebook page is about sharing the latest research findings, and also people’s experiences, while providing an avenue for people to reach out for support.
Identifying frost
Fortunately, Ms Morgan says, 2023 did not produce a widespread significant frost, so the resource package stayed on the shelf.
“It was great that it didn’t have to be rolled out to its full capacity, but we did use bits and pieces and we’re ready to go in the event that we get another big state or region-wide frost event,” Ms Morgan says.
Figure 1: Susceptibility of wheat to frost during the development cycle.
In place of a major frost in 2023, growers across the Mallee endured several smaller events which had varying impact on grain quality and yield. This highlighted the need for information around frost identification.
“Frost identification is still really hard, especially when it’s not widespread because you need to know where to look,” she says.
One of those looking was Lower Eyre Peninsula agronomist George Pedler. Appreciating the challenges around identifying frost damage, he uploaded a video to the Better Frost Decisions Facebook page soon after a localised frost event, showing growers the tell-tale signs.
A quick response
Ms Morgan says it is critical to identify frost as quickly as possible. This will ensure timely decisions can be made bringing growers maximum value. For example, a frosted crop destined for hay needs to be cut as soon as possible to ensure it maintains its quality.
“The longer you leave it, the more the quality drops, so a fast response is really important if you are cutting for hay,” she says. “You need to know quickly how bad it is so you can make that decision.”
Similarly, an accurate diagnosis will ensure inputs such as fertilisers and fungicides aren’t wasted on a frost-damaged crop. It could also help to gain maximum value from grazing a crop rather than taking it through to grain.
In response to the 2023 frost events, experts conducted live Facebook sessions, inviting questions from and fostering engagement with growers. Agricultural strategist Kate Burke addressed mental health issues, while COtL Mesonet co-founder Damon Grace explained how to use his company’s weather stations.
These live events and other uploads provide information in accessible “short bursts” and help to increase awareness of the issues, providing practical as well as emotional support when it is most needed, Ms Morgan says.
A proactive approach
As well as helping growers to best respond to frost, the project also took a proactive approach, looking at mitigation. And this is demonstrated by the work MSF is doing with the four farming systems groups.
- With AIR EP it is looking at how sowing times and variety choice can reduce the impact of frost;
- Upper North Farming Systems is using sensors to develop frost maps for paddocks, identifying high-risk areas for targeted frost mitigation management;
- Southern Farming Systems has developed a frost economic calculator that enables modelling based on a range of scenarios; and
- Birchip Cropping Group is looking at manipulating the flowering time of crops with grazing.
Better Frost Decisions newsletters and podcasts featuring agronomists and growers have been created, summarising this work and communicating insights and findings to growers. And a range of case studies featuring different frost management strategies are also being completed.
The investment concluded in March, and the frost response materials are ready to be rolled out when needed. The Facebook page will continue to be updated, providing an accessible archive of resources over time.
Figure 2: While bigger canopies and stubble retention provide significant benefits, they can increase the severity of frost by reducing the amount of sunlight and heat absorbed by the soil – heat that at night can behave like a buffer against frost. Source: Swella, 2013
GRDC southern region grower relations manager Bek Starick says investments such as this are critical extension tools, ensuring growers have access to the most up-to-date advice and resources on identifying and managing frost in their regions.
“We understand how devastating frost can be and how important new management strategies – and discussing those strategies – are to growers on-farm,” she says. “It’s giving them more tools in their tool kit to manage frost better, because as something that is outside of your control as a producer it’s an issue we continue to grapple with.”