The challenge
The Tararua District is home to some of the most efficient, low-intensity dairy farms in the country. Despite this, these Tararua dairy farmers are faced with a need to make significant environmental reductions to achieve community objectives and regulatory requirements.
To gain consent, 118 of these Tararua farmers are faced with reducing nitrogen leaching by an average of 60 percent to meet targets outlined in the Horizons Regional Council One Plan. It’s a massive challenge, but in a new approach, DairyNZ and partner organisations are working with farmers in the catchment to help them lead their own solution.
The Tararua Plantain Rollout project addresses this challenge by using plantain as an environmental forage. Research has proven the environmental qualities of plantain to reduce nitrogen leaching, and the project seeks success through plantain adoption at both farm and catchment level.
Alongside quantified gains in water quality, the project serves as a case study for the rapid adoption of new technology (namely plantain), and as a blueprint for catchment environmental programmes which address both farm business and community objectives.
The Tararua project began in the 2018-19 season and will run for five years.
Backed by Research
The Tararua Plantain Project capitalises on research findings from the DairyNZ Forages for Reduced Nitrate Leaching (FRNL) programme and the PGG Wrightson Seeds Greener Pastures programme which established that plantain (cv. Tonic) reduces the concentration of nitrogen in urine, and subsequently reduce nitrogen leaching from cows’ urine patches. Research continues through the Plantain Potency and Practice programme, building on this earlier research, and the learnings from the Tararua Plantain Project.
Project support
Massey University
Professor Peter Kemp, Soledad Navarrete and David Horne from the School of Agriculture and Environment are carrying out research at a university farm, measuring N leaching from plantain pastures compared with ryegrass pastures. They’re supporting farmers by sharing the results of this research. In turn, Tararua farmers are contributing to the Massey research by evaluating ways to best integrate plantain into their farm systems.
Horizons Regional Council
Dr Nic Peet, Horizons strategy and regulation manager, says the project’s success will help drive water quality improvement in the Manawatu River and help farms meet regulatory requirements to reduce N.
“Without tools like the use of plantain, farmers in much of the Tararua are unlikely to meet the One Plan N-leaching targets and remain viable. The plantain project is important and has the potential to make a significant difference – economically and environmentally.”
MPI
The Tararua Plantain project is supported with funding from MPI, through the Sustainable Farming Fund. MPI project funding is gratefully received by the project for a three year period July 2019 – June 2022.
Fonterra and Nestlé
Fonterra and its customer Nestlé have helped to expand the trial through additional funding and by sharing expertise. The collaboration is helping to accelerate uptake of plantain, with more farms getting onboard and increasing the amount they grow, therefore maximising the benefits. Fonterra and Nestlé wanted to support the Tararua Plantain Project given their respective commitments around sustainability.
Early adopters
Tararua dairy farmers Blair Castles, Mark Diamond and Brad McNaughton are already using plantain in their pastures. As System 2 and System 3 farmers and members of the project’s monitoring group, they’re keen for others to learn from their results.


Led by DairyNZ, the Tararua Plantain Project is helping unconsented farmers keep on top of nitrogen leaching. (Left to right: DairyNZ project manager Adam Duker and local dairy farmers Mark Diamond, Blair Castles and Brad McNaughton).