A BUMPER crowd of more than 60 farmers, growers and Western Sydney University agriculture students turned out to the final field day for the Greater Sydney Local Land Services Next Generation Compost Trial at Richmond last week.
The event marked the end of the EPA-funded project which investigated the best use of recycled organics in horticulture, with the aim of weaning Sydney Basin farmers off their dependence on poultry manure.
The project was about assessing the difference between vegetable crops grown with just compost, just fertiliser, and with a range of compost and conventional fertiliser blends.
Plant nutritionist Dr Geoff Cresswell said the most consistently effective compost treatment in the trials had been the compost combined with a slow-release nitrogen fertiliser.
“Some short-term benefits of using compost at this site were to improve root health and structure, lower nutrient-leaching losses and to stimulate beneficial soil biology,” Dr Cresswell said.
While they were only seeing the short-term benefits, he felt the full impact of compost use would only be seen over time. “Our experience suggests that the full benefits of compost on soil health and crop yield will become obvious after long-term use,” he said.
As part of the project the University of Technology’s Institute for Sustainable Futures (UTS:ISF) conducted research into consumer interest and demand for compost-grown vegetables.
UTS:ISF Research Director Dr Brent Jacobs said there was genuine interest from both growers and the community in the potential of recycled organics.
“Our research showed a general belief that compost-grown vegies were better for overall soil health and the environment, and more than half of consumers surveyed considered compost use extremely important, which shows there is a genuine demand out there.”
With the results in, and the most beneficial blend of compost and fertiliser identified, the challenge now is to get compost companies to manufacture and market the product at an affordable price for farmers.