IMPROVING VEGETABLE FARMING PRACTICES THROUGH RESEARCH

Helena O’Neill

Researchers are gearing up to plant their first lot of crops as part of a three-year project looking at the impact of growing vegetables regeneratively.

The project, led by LeaderBrand Produce, Countdown, and Plant & Food Research Limited (PFR), is the first industrywide collaboration investigating regenerative vegetable farming practices, particularly in relation to productivity, profitability, people and environment.

LeaderBrand general manager of farming, Gordon McPhail, says the strong research focus of this project will help to create tools that will allow vegetable growers to make informed decisions about implementing regenerative farming practices of their own.

The trial site will run next to a control site on LeaderBrand’s vegetable production operation in Gisborne to compare the impacts of regenerative practices over time.

“Trial areas will depend on the final decisions on the treatments and evaluation methods but are likely to be between one and five hectares per crop rotation type,” Gordon says. “It is important we can prove and replicate this on a commercial scale.”

Compost will be applied ahead of overwintering crop plantings made from next March.

“We started talking with Countdown about sustainable vegetable production and things we have done and could do to improve but also [to] pave the way for others,” Gordon says.

Gordon says LeaderBrand has been working with service crops and composts for several years and the project is an opportunity to build on that. Service crops are cover crops grown in agroecosystems for the ecosystem services they provide rather than as a harvestable product, e.g., increased crop water supply.

“We’ve already been working hard in this space and this joint project will allow us to build on some of our previous and current projects. Having evidence-based solutions for integrated pest management (IPM), nutrient budgeting, soil management and crop rotation is a game changer.”

The service crops will include LeaderBrand’s previous green manure crop options (barley, oats and sorghum) and in-field and field margin floral resources (buckwheat, alyssum and phacelia).

Gordon says PFR is currently reviewing options for two vegetable rotations: one for overwintering service crops following a summer crop (e.g., broccoli, squash, sweet corn, or watermelons) and the other for summer-grown service crops supporting winter vegetables like leafy salad crops.

PFR are reviewing the science that is needed to build a decision support tool for a selection of service crop species based on their seasonal growth characteristics, the beneficial species that they support, the pests they share with vegetable crops in the rotation and their soil health benefits (e.g., organic matter content, rates of breakdown and nutrient release).

“They are here to design scientifically robust plot trials — comparing service crop species and management techniques — ensuring that the data collection is accurate and relevant,” Gordon says. “The results will form the basis of the decision support tool that they will build.”

PFR are also looking at the existing research and literature already available and how this may relate or enhance the trial, Gordon says.

The project started with an assessment of nutrient release characteristics from compost applied at various rates on