University of Minnesota Extension explains why unplanted fields from last year may be at risk of fallow syndrome in 2020 and why a low rate of "pop up" starter fertilizer could be the best management strategy.

If you're seeing purple corn this year, do some investigation and avoid making assumptions about the cause, says North Dakota State University Extension.

If crop color remains poor even after a week of drying soils and good growing conditions, then it is possible that N movement to below the rooting depth is affecting the ability of the crop to grow out of this problem.

With the variation in conditions we have seen this spring there are a few issues that may show up in fields related to cool and wet soils. Purpling of corn leaves due to phosphorus (P) deficiency and early season interveinal striping due to sulfur (S) may occur if temperatures remain cool and we continue to have frequent rains.