By Jim Camberato
Starter fertilizer is the placement of fetilizer near or with seed at planting. Tradional starter fertilizer placement has been two inches below and two inches to the side of the seed and is termed 2X2 placement. When in this position, the seedling roots encounter the fertilizer shortly after emergence. Different starter fertilizer placements, positioned both vertically and horizontally from the seed, are possible. In-furrow fertilizer, often referred to as pop-up, is an alternative to 2X2 placement that involves less hardware, cost, and lower amounts of fertilizer. Placement with the seed may result in earlier nutrient utilization by the plant than 2X2 placement.
In previous research, starter fertilizer often accelerated the early growth of corn, resulting in taller corn and more dry matter. Sometimes early gowth responses resulted in increased grain yield, but sometimes they did not. Grain moisture was sometimes lower with starter fertilizer than without, even when grain yield was unaffected.