Environment Waikato has secured a $324,000 grant from the government’s Sustainable Farming Fund for a trial into how effluent can be used to boost maize growth.
“This is very exciting for us because it’s a New Zealand first,” Environment Waikato sustainable agriculture coordinator Gabriele Kaufler said.
“Overseas research shows effluent can be used very effectively to grow maize and we want to make sure this technique gets picked up in New Zealand. It’s about helping our farmers connect with knowledge that’s already out there.”
The grant was the result of four on-farm field days the council has run over the past year in conjunction with industry and research groups, involving demonstrations on four Waikato farm paddocks.
Half of each paddock was treated with commercial fertilser and the other half with dairy effluent plus a small amount of fertiliser to make sure crop nutrient requirements were met.
Soil tests down to 90 cm and effluent nutrient tests were carried out, with crops monitored throughout the growing season.
“The crop yield measurements showed the effluent blocks grew just as much maize but used less commercial fertiliser and one farmer was actually saving $320 per hectare,” Ms Kaufler said.
“We are very grateful to the innovative farmers who were willing to support us with these initial investigations, which have helped us to leverage significant funding from the government for the next stage of research.”
In conjunction with the project team, Environment Waikato is now about to launch trials that will take a more scientific approach to growing maize with effluent. Four farms from each of the region’s major maize growing areas will be involved.
Driven by a project team of farmers, Environment Waikato and industry representatives, the trials are aimed at raising farmers’ awareness of nutrient management issues.
“We discovered during our on-farm field days that a lot of farmers aren’t aware of the value of effluent produced on their farms and how much nutrient they were applying by spreading it,” Ms Kaufler said.
“Feedback from these field days showed they had considerably increased farmers’ awareness of using nutrients more efficiently, as well as the risks of nutrient overloading on paddocks.
“These new trials are about putting some hard science around that and communicating to farmers that effluent is not just a waste product that has to be got rid of – it’s liquid gold.
“We are also very interested in the implications for farm systems. For example, growing maize means the paddock can’t be grazed for at least eight months, which impacts on how the farm is managed. We will have field days to look at each trial, which will give the wider farming community the opportunity to further discuss this approach.
“The information farmers will bring to the table during these trials will be invaluable,” Ms Kaufler said.