Looking to be more sustainable in how he manages his farm, particularly in terms of nitrogen management, South Canterbury arable farmer Andrew Darling is one of the first to participate in a new Foundation for Arable Research (FAR) initiative.
As nitrogen fertiliser, his biggest spend, has at least doubled in price in the past two years, he wants the confidence to cut back and do more to utilise nutrients already in the soil.
The FAR initiative, called Growers Leading Change (GLC), provides a farmer-led framework for arable farmers to develop, test and introduce new ideas, technologies, and ways of working, in order to improve their farm, industry and community sustainability.
As part of this, Darling’s farm is the South Island’s first GLC Pathfinder, or demonstration farm, aimed at growers who are ready to embrace new ideas and technologies and identify sustainable pathways for the rest of the sector.
Andrew and his wife Amy lease Poplar Grove Farm from his parents Warren and Joy Darling.
The rolling downs farm is fairly typical for an arable farm south of Timaru in the type of crops it grows.
The biggest area is grown in feed wheat and barley. Sunflowers and oil seed rape are supplied to Rolleston-based Pure Oil for processing into high-value cooking oil. Turf ryegrass for seed and fava beans are also grown.
Darling is questioning their high-cost, high-input cropping programme in favour of an approach that is less prescriptive, more responsive to the season and better utilises the soil nutrients and beneficial insects already available on the farm.
The Darlings have already moved to adopt this approach, using 1ha grid soil sampling for the last seven years and using this information to apply nutrients at variable rates across paddocks.
Dual sensor cameras installed last season on the roof of their tractor automatically varied nitrogen application rates depending on a crop’s density and greenness. The cameras are calibrated to the type of crop and growth stage.
This, along with soil nitrogen testing reduced nitrogen applications by 15 per cent last year, compared to the blanket rate, with no impact on yields.
FAR senior researcher cereals Jo Drummond said nitrogen fertiliser is the biggest on-farm cost, so it is important for growers to make sure it is being used in the most efficient way possible.
“It’s great to see Andrew and Amy using tools and technologies to really understand soil supply and crop uptake, which can provide opportunities to cut back on fertiliser use without compromising on yield and profitability.
Likewise, understanding the population dynamics of beneficial predator and parasitoid species can reduce the need for foliar insecticides, not just on your own farm, but across a region.”

Field day details:
Tuesday September 27, 111 Timaru-Pareora Highway, from 10am to 12 noon.

• By Pat Deavoll