Faster Emergence for Early Season Planters

Starter fertilizer helps crops overcome late-season stress

A stretch of unseasonably warm days encourages many farmers to get out in the field and plant early, especially farmers with a lot of acres to cover. Getting in the field early can reduce the risk of planting delays but presents some challenges, as well.

When farmers plant early, they face cooler soil temperatures and damper conditions, and there is often not enough phosphorus (P) available to a young, rapidly growing crop. One way to address the challenges of early planting is to apply a starter fertilizer.

Starter fertilizer provides a readily available source of P that the plant can access as soon as it germinates, as well as a supply of micronutrients like zinc, magnesium and boron, which help support more efficient P uptake. This is critical to early crop vigor, which translates into more rapid root growth and development. Plants with better root systems can explore a larger volume of soil to compete for nutrients and use water more efficiently. These faster-emerging plants are more robust, with a larger leaf area, larger stalks and a better tolerance of environmental stresses – all qualities that lead to higher yield potential.

Many starter fertilizers use high concentrations of ortho-phosphate, the plant available form of P. While ortho-P is plant available, it is also a very active form. This means it can be readily fixed in the soil when it reacts with iron, aluminum, calcium and magnesium. Depending on conditions, an average of 75 percent of applied P can get tied up in the soil, making it unavailable to the plant during the season. That makes managing P challenging to growers because they can’t know if they are getting the applied P into this year’s crop.

In order to maximize the availability and efficiency of P fertilizer to the crop, farmers should use the 4Rs of nutrient management, applying the right rate, at the right time, in the right place with the right source. The 4Rs are critical, but phosphates (especially high-ortho-P starters) are so reactive and readily tied up in the soil, farmers may want to look at tools to protect applied P from being fixed in a form that can’t be taken up by the plant. Some of these tools are covered in the audio clip below discussing the benefits of starter fertilizer and the challenges when working with P.