CCC Fertiliser & Sediment Management Insights
More than 80 mg/L nitrogen could reduce blueberry fruit yield
Published 3 Feb 2026
Adding more than 80 milligrams of nitrogen per litre in fertigation could reduce fruit production in blueberry crops, according to new CCC research. The research has also shown average Brix levels (sugars) and individual berry weights across the season did not change despite the rate of nitrogen applied (for rates ranging from 40 up to 120 mg/L nitrogen).
Second year update on macadamia soil amendment trials
Published 28 Oct 2025
Results from the second year of long term macadamia orchard soil amendment trials have shown no significant differences in yield or nut quality between macadamias grown with organic soil amendments, when compared to macadamias grown only with conventional chemical fertilisers. However, the Clean Coastal Catchments research team expects the broader benefits of organic amendment applications will become more apparent in coming seasons.
Using biochar to boost nutrient retention in blueberry substrates
Published 12 Sept 2025
Early research results demonstrate that adding biochar to potted blueberry substrate can increase the capacity to hold and store key plant nutrients such as nitrogen and phosphorus. In a production system where nutrient application is closely matched to plant requirements, the nutrients stored in the biochar could provide a buffer of nutrition accessible to the plant.
Capturing nutrients at the CCC Blueberry Research Facility
New filters have been installed by the CCC team to capture phosphorus in blueberry crop waste water. Our researchers are collecting data on the effectiveness of dolomite based filters, building on previous research on the capture of excess phosphorus, nitrate (NO3-) and ammonium (NH4+) using bioreactors and reedbeds at the CCC Blueberry Research Facility at the Wollongbar Primary Industries Institute.
Assessing the benefits of organic nutrition for macadamia production
Long term trials of organic soil amendments in macadamia production were established by the Clean Coastal Catchments (CCC) Research project in 2023. The trials have now been underway for almost eighteen months at the NSW Centre for Tropical Horticulture near Alstonville.
Leaf analysis as a tool for managing southern highbush blueberry crops
Advice from Dr Sophie Parks on the use of leaf analysis to diagnose problems in blueberry crops, along with a CCC Research update on the nutrient status of southern highbush blueberry in Australia.
Developing nitrogen fertiliser guidelines for NSW blueberry growers
The CCC Research project is investigating the nitrogen needs of Southern Highbush blueberry grown as an evergreen crop on the NSW north coast. Experiments are currently underway at the Wollongbar Agricultural Institute to determine the ideal amount of nitrogen for maximum productivity and fertiliser efficiency.
A review of nature-based systems (bioreactors and wetlands) to treat blueberry irrigation runoff
The CCC Research project is assessing the effectiveness of nature-based systems for the removal of nitrogen from crop irrigation run off at the Wollongbar Primary Industries Institute. The trial began in 2023 with the installation of three bioreactors and one reed bed installed at the Wollongbar Blueberry Nutrition Research Facility to treat nutrient rich run off from 300 potted blueberry plants.
Improving the management of soilless growing media for potted Southern highbush blueberry, an Australian case study
This paper was presented by Dr Sophie Parks at the International Vaccinium Symposium, Nova Scotia Canada. Dr Parks is a Senior Research Scientist with the NSW Department of Primary Industries and leads the Clean Coastal Catchments blueberry nutrition research team.
Macadamia nutrient replacement values and varietal variation
CCC research on macadamia crop nutrient replacement values, aimed at improving fertiliser efficiency and reducing diffuse pollution, has been published in Department of Primary Industries grower guides targeting macadamia nutrition and soil health.
A study of seasonal leaf nitrogen in southern highbush blueberry grown as an evergreen crop in Australia
This paper was presented by Dr Sophie Parks at the International Symposium on Mineral Nutrition of Fruit Crops. Dr Parks is a Senior Research Scientist with the NSW Department of Primary Industries and leads the Clean Coastal Catchments blueberry nutrition research team.
Greenhouse drain water recycling in protected cropping - the rewards and the realities
NSW DPIRD Research & Development Officer Luke Jewell looks at the benefits and challenges involved in retrofitting irrigation reycling in the protected cropping sector. Converting to a closed recycling hydroponic system can dramatically cut water use and reduce fertiliser inputs, but careful planning is needed to avoid risks to production.
Blueberry Nutrition: The Right Nitrogen Source
Dr Sophie Parks discusses the efficacy of various sources of nitrogen in fertigated blueberry production. As Dr Parks explains, supplying the 'right source' of nitrogen is the first step in the 4Rs approach to plant nutrition.
Options for erosion control in old dark macadamia orchards
NSW DPIRD Soil Scientist Justine Cox and Development Officer Jeremy Bright review the current recommendations for reducing soil movement in macadamia orchards and outline their research on mulching options to lower the risk of sediment and nutrients moving off farm into water ways.
Towards a better understanding of Nitrogen loss pathways and fertiliser management
Dr Lukas Van Zwieten evaluates the effectiveness of enhanced efficiency nitrogen fertilisers, the benefits of slow release fertilisers, organic amendments, and biological nitrogen fixation, and the development of rapid testing for potentially mineralizable nitrogen (PMN), with regard to their role in improving productivity and reducing nutrient pollution
Why understanding soil texture is key to blueberry mound management
NSW DPIRD Soil Scientist Justine Cox discusses the significance of soil texture in managing blueberry mound nutrition. Considering soil texture is equally as important as testing for soil nutrients, as soil texture critically affects the plant’s capacity to access nutrition applied through fertigation.
