Phosphorus Fertilizer Efficiency

Crop uptake efficiency of fertilizer phosphorus is very low because of the many ways that fertilizer phosphorus (which is 100 percent water soluble) can change to less available forms. Fertilizer efficiencies are affected by several factors.

1. Amount of phosphorus applied

2. Soil characteristics (pH, organic matter, texture, etc.)

3. Type of crop and root characteristics

4. Degree of soil phosphorus deficiency

5. Method of phosphorus application

6. Soil temperature and moisture

In the year of application, corn, sorghum, or soybeans will generally use less than 10 percent of the applied phosphorus. Wheat, however, has shown efficiencies of up to 30 percent. This efficiency was attained on a very low available phosphorus soil and was achieved with seed-applied phosphorus. Utilization of broadcast phosphorus application was less than 10 percent.  For more detail, please refer to the article, 'Phosphorus,' in Nutrient Management for Agronomic Crops in Nebraska.