Modifying release of nitrogen: A demonstration from Dean, Victoria

As fertiliser efficiency and environmental sustainability continue to shape potato production, a key issue remains: how best to balance inputs with crop performance?

The Dean demonstration site

At the Dean demonstration site in Victoria’s Ballarat region, PotatoLink worked with local grower Kain Richardson to investigate whether nitrification (N) inhibitors could improve yield and quality while reducing production risks.

The site was somewhat sloping, with red clay soils. The 2024-25 season was unusually dry, with water supplied through managed pivot irrigation and no major leaching events.

This likely limited the impacts of the nitrification inhibitors that were tested.

It should also be noted that, although some differences were recorded, this was not a replicated research trial. Moreover, the site was not homogeneous, limiting inferences that can be made from these results.

The Dean demonstration site, near Ballarat, Victoria

Site assessments at a glance

• Location: Dean (Ballarat region), Victoria

• Soil type: Red clay

• Crops on farm: Rye, canola, pasture, potatoes

• Assessments included:

  • Yield (total and marketable)

  • Defect and small tuber incidence

  • Tuber size distribution (by weight and count)

  • Stems and tubers per plant

  • Specific gravity and dry matter for processing suitability