Source: ILSoyAdvisor.com

If you expect more from your soybeans, maybe they are expecting more from you. 

If you can’t answer “yes” to the following questions, fertility management could be holding back your soybean yields:

  1. Do you soil test at least every 4 years?
  2. Is your percent base saturation for potassium (K) 3% or greater?
  3. Are you tissue sampling for micronutrient deficiencies and hidden hunger?
  4. Are you maintaining a soil pH in the mid 6s?
  5. Do you apply phosphorus (P) and K every year on your soybeans?
  6. Do you apply any sulfur?
  7. Are you applying enough fertilizer to replace what record yields are removing today? 
  8. Have you ever applied any micronutrients, such as boron, zinc or manganese?
  9. Have you ever tried any foliar nutrition products?
  10. Do you have a specific fertility management program for soybeans in place? Or are they supposed to get by on what your previous corn or wheat crop didn’t use?

Does it surprise you that a 75-bushel soybean crop removes 227 pounds of nitrogen (N), 150 pounds of potash, 98 pounds of phosphate, 15 pounds of sulfur, 2.6 pounds of zinc and 2 pounds of boron? This is just the amount of nutrient that is removed with the grain as it leaves the field. The plant actually needs and takes up far more than this, but the rest of it is recycled back to the soil as the leaves, stems and roots decay.  

Soybeans actually use far more N than they fix through their nodules. Enabling a soybean to fix more N during seed fill could increase soybean yields. Soybeans can scavenge for nutrients, but you should consider the fact they might yield more if adequate amounts of essential nutrients are readily available.

In addition to selecting the right varieties, managing diseases, planting early, utilizing seed treatments, controlling weeds before they exceed 4-6 inches in height, planting in narrow rows and minimizing harvest losses, don’t overlook the basics of soil fertility and plant nutrition when you are striving for higher soybean yields.