Project overview
Declining rainfall and water-repellent soils can limit crop productivity across Western Australia’s Wheatbelt. Crops use only around 56% of available water in many systems, with much lost to runoff or evaporation. Improving how rainfall is captured and stored in the soil offers a clear opportunity to reduce crop water stress and improve yields.
The SMART SPRAYS project is addressing this challenge by testing a novel, non-toxic, bioplastic-based soil spray designed to improve water harvesting into furrows and water retention in the plant root zone.
The aim is to capture rainfall more effectively, keep it where crops can access it for longer, and reduce the risk of water stress during the growing season, using an approach that can be integrated into existing broadacre farming systems.
Led by Murdoch University in collaboration with SoilsWest, Ecopha Biotech, and Bangor University (UK), the project has progressed from laboratory studies to field-scale trials across diverse agroecological zones.
Impact and results
SMART SPRAYS form a thin, biodegradable water barrier that can be applied using standard farm spray equipment, lowering barriers to adoption. When applied to soil mounds, the spray helps direct rainfall into furrows, reducing evaporation losses and improving infiltration where crops need it most.
Field trials in Merredin (in partnership with the Merredin & Districts Farm Improvement Group), Esperance (in partnership with the South East Premium Wheat Growers Association), and Yuna (in partnership with the Yuna Farm Improvement Group) have tested polymer spray and hydrogel formulations, providing insights into performance across different soils and climates. Laboratory studies showed that bioplastic film thickness critically influences evaporation and infiltration, informing product design and field application strategies.
Grower engagement has been central to the project. Presentations at grower group spring field days, alongside targeted surveys of farmers and agronomists, have supported awareness raising and informed adoption modelling using the CSIRO ADOPT framework. This work is helping identify where SMART SPRAYS are most likely to deliver value, and what practical or economic barriers may need to be addressed for broader uptake.
Looking ahead
In collaboration with the Grains Research and Development Corporation and other partners, the project is now laying the groundwork for scalable, location-specific solutions that could improve water availability in Western Australian cropping systems. By improving how rainfall is harvested and retained in water-limited environments, SMART SPRAYS offer a promising pathway to building more resilient and productive grain farms under increasing climate pressure.
This project is supported by the South-West WA Drought Resilience Adoption and Innovation Hub, through funding from the Australian Government’s Future Drought Fund, Murdoch University and the WA Agricultural Research Collaboration
FAQs
Why SMART SPRAYS?
Smart sprays have the potential to reduce evaporation and redirect water for increased crop yield and profit.
Smart sprays components:
- Biodegrade in marine, soil, and compost environments into CO₂, water, and biomass.
- Do not degrade into microplastics in the environment.
- Reduce reliance on fossil fuels and have a decreased carbon footprint as no fossil fuel feedstock is used.
- Do not need to be retrieved from the field – they will biodegrade in situ.
The main component of SMART SPRAYS can be produced by microorganisms through the use of a wide variety of renewable feedstocks, like organic wastes, waste canola oil, brewers waste and glycerol, creating a circular economy.
What’s the different between plastics and bioplastics?
Plastics and bioplastics can be categorised based on their origin/feedstock (biobased vs. fossil fuel based) and their degradation properties (biodegradable vs. non-biodegradable).
Feedstocks
Fossil-based feedstocks: Derived from petroleum, natural gas, or coal.
Biobased feedstocks: Derived from plants, algae, or agricultural waste products.
Differences in degradation
Download the fact sheet to learn more about plastics and bioplastics.
What’s the different between compostable and biodegradable?
Biodegradable materials are those that can be fully broken down into natural substances, such as water and carbon dioxide, by naturally occurring microorganisms. In waste management, the term “biodegradable” is broadly used to describe materials that degrade either under composting conditions or in the natural environment. The key distinction is that compostable materials are designed to break down within a specific timeframe under controlled composting conditions, where factors like temperature, moisture, and microbial activity are optimised to accelerate decomposition and biomass formation.
Certified compostable
Compostable refers to a product’s ability to biodegrade into non-toxic, natural elements within a defined timeframe under specific composting conditions. Both fossil-based and bio-based bioplastics can be certified as compostable. However, compostability claims should only be made if the product has been certified to a recognised standard, such as Australian Standards AS 4736-2006 or AS 5810-2010.
Biobased bioplastic biodegradable
Smart sprays belong to this category.
Bioplastics made from bio-based feedstocks that fully break down into natural substances, either under composting conditions or in the natural environment. PHA bioplastics, in particular, are known to degrade effectively in both soil and marine environments.
Fossil-based bioplastic biodegradable
Fossil-based biodegradable plastics make up a relatively small category, which includes materials like PBAT and PCL. While PBAT is both biodegradable and compostable, improper disposal can still have environmental consequences, as its degradation requires specific conditions to occur efficiently.
Biobased bioplastic non-biodegradable
Bioplastics can be derived from bio-based feedstocks while remaining non-biodegradable. These materials are chemically identical to traditional fossil-based plastics.
Conventional plastics non-biodegradable
These materials do not biodegrade. In Australia, 2.9 million tonnes of plastic waste are discarded each year, with only 13% recycled, while the remaining 87% ends up in landfill.
Reference: State of Bioplastics in Australia, CSIRO, 2024 with permission.
Download the fact sheet to learn more about plastics and bioplastics.
News
- Article, Field Notes, Regional Nodes, Transformation Murdoch
- Article, De-risking the seeding program, Field Notes, Innovation Farmanco, PropaGATE, Regional Nodes, Showcase, Transformation Murdoch, Transformation Whole, X-hub Contour Consulting
- Article, Transformation Murdoch
- Article, Transformation ECU, Transformation Farmanco, Transformation Murdoch, Transformation UWA dams, Transformation UWA Natural Capital, Transformation Whole
- Media Release, Innovation Farmanco, PropaGATE, Regional Nodes, Showcase, Transformation Murdoch, Transformation Whole, X-hub Contour Consulting
- Article, Regional Nodes, Transformation Murdoch
- Article, Field Notes, Transformation Murdoch
- Media Release, Transformation ECU, Transformation Farmanco, Transformation Murdoch, Transformation UWA dams, Transformation UWA Natural Capital, Transformation Whole
Resources
- Webinar
- Podcast
- Webinar
Additional resources
Collaborators
Project team
Professor Daniel Murphy
Murdock University
Cheryl Rimmer
Murdoch University
Samantha Vijoen
Murdoch University
Alex Gulizia
Murdoch University
Joseph Boctor
Murdoch University
Associate Professor Fran Hoyle
Murdoch University
Lucy Tomassini
SW WA Hub
Contact
Professor Daniel Murphy
Director, Centre for Sustainable Farming Systems Professor of Agricultural Microbiology, SoilsWest Director, Bioplastics Innovation Hub
daniel.murphy@murdoch.edu.au
Lucy Tomassini
Project Manager, South-West WA Drought Resilience Adoption and Innovation Hub
lucy.tomassini@gga.org.au