Importance Of Potassium In Soybeans

Soybeans have a big appetite for potassium, writes agronomist Dan Davidson on ILSoyAdvisor.com. So, are you feeding them enough?

Soybeans require potash and plenty of it and remove more than corn. A 200-bushel corn crop will remove 50 lbs. of potassium per acre, while an equivalent 70-bushel bean crop will remove 84 lbs. How much attention do you pay to making sure potash levels are adequate before you plant your soybean crop?

Advertisement

Many growers have routinely applied fertilizer before two successive crops of corn and let their soybeans scavenge for leftovers. We all know what happens to pigs that become the runts of a litter — they always get the leftovers and remain small their entire lives.

Top Articles
Ranch Systems Is a Recipient in the 2024 Digi Green Tech Awards

The problem with potassium is that what you apply is not necessarily readily available to the second-in-the-rotation soybean crop, especially 18 months after you apply it. When managing your potassium program, consider the following:

  • Potassium is relatively immobile in the soil, so availability depends on location and soil characteristics.
  • No-till and minimum tillage methods, as well as compaction, can limit root growth and access to potassium.
  • No-till can stratify potassium near the surface, above the root zone.
  • Soil temperature, pH and moisture impact potassium availability.

Read the full story on ILSoyAdvisor.com.

0

Leave a Reply

Avatar for George Rehm George Rehm says:

This article attempts to leave the perception that farmers are short-changing the nutrient requirements of the soybean crop and uses crop removal to support this perception. I respectively disagree. Using crop removal as the basis for fertilizer recommendations is the most expensive approach to fertilization. Research does not support this approach. There is no question. Fertilizer decisions should be based on soil testing with decisions based on correlation and calibration research. And incidentally, potassium availability is not related at all to soil pH.

George Rehm
Nutrient Management Specialist (retired)
University ofMinnesota

Advertisement
Advertisement