Ideas, information and insights from real farmers on effective crop nutrient management strategies.

How should a farmer sample for diagnostic purposes?

Like most production issues, nutrient deficiencies rarely affect an entire field. When there are areas that are exhibiting suspected nutrient issues, here is the best way to go about determining what the likely issue is. Ideally, plant tissue and soil samples should be collected for… Read More

What is the optimum pH for legume crops like soybean and alfalfa?

Compared to corn, legume crop production thrives under slightly higher pH (6.2 to 6.8). Legumes, like soybean and alfalfa, form symbiotic relationships with rhizobia to form nodules in roots that biologically fix nitrogen. If the soil pH is too low, this can negatively affect the rhizobia… Read More

Why is phosphorus immobile in soil?

In general, phosphorus is immobile in soil due to the chemical bonds a phosphate ion can form. Phosphorus from commercial fertilizer and soluble phosphorus in the soil — phosphate — is either present as H2PO4¯ or HPO4¯2 when the soil pH is near neutral. These are… Read More

How does potassium help plants regulate moisture?

To put it simply, potassium regulates the opening and closing of plant stomata. Stomates are the pores on plant leaves that allow for gas and water vapor exchange. When plants have adequate potassium, the guard cells swell and allow for complete closure of the stoma… Read More

Is there a difference between phosphorus soil test methods?

In short, yes, there are differences in methods. The phosphorus soil test is an index of phosphorus availability, which ultimately tells a farmer the likelihood of a response to fertilizer application. Universities have conducted many site years of research correlating plant available phosphorus in soil… Read More

Ask an Agronomist

  • This field is for validation purposes and should be left unchanged.