The South Island Agricultural Field Days kick off on Wednesday at Lincoln University Farm.
The event, the largest of its kind in the South Island, usually attracts 20,000 to 25,000 spectators over the three days.
The theme for this year's field days is Ag-Technology and there will be more than 400 exhibitors displaying the latest farm technology, machinery and ideas.
Also starting on Wednesday, is the Dairy Women Network's conference in Nelson.
Three hundred farmers and farm managers are expected to attend two day event which has the theme 'taking down the boundary fences'.