As plants use P from the soil solution it s replenished from the exchangeable P pool in the soil. Soil test levels don t necessarily reflect how much can become available to a crop from the soil reservoirs of organic and exchangeable phosphorus. Some growers recently reported that use of only starter fertilizer was able to fully meet sugarbeet crop P requirements for growth. Recent University of MN research by Smith and Sims supports these claims, Figure 2. The soil test at the research site was 5 ppm.
P is more efficient.
Smith and Sims used 3 GPA of starter plus 3 GPA of water for better application uniformity and less risk of stand loss. Detailed discussion of University of MN starter fertilizer research is available in the 1999 and 2000 Sugarbeet Research and Extension Reports. On the next screen, zoom into an area of interest. If it is a township, type in the township in the form, 150-48 for example then click on the zoom button. The next step is to click on query to see what images are available.