ANNAPOLIS, MD – The Maryland Department of Agriculture today announced that farmers who planted small grains for harvest last fall may “top dress” these crops with commercial fertilizer beginning February 25, as long as ground conditions remain favorable and in accordance with their nutrient management plans. The determination follows Maryland’s nutrient management regulations and is based on research conducted by University of Maryland plant experts. As a reminder, manure may not be applied to fields until March 1.
Each year, University of Maryland researchers examine soil temperatures and crop growth over the winter to estimate when small grains will emerge from dormancy. This measurement, known as Growing Degree Units, is used to determine when small grains will benefit from spring nitrogen applications. According to data collected by University researchers, commercial fertilizer may be safely applied to small grains beginning February 25. At this time, these plants will have absorbed all available nutrients in the soil and will require additional nutrients to keep growing.
“The winter of 2017-2018 has been interesting,” said Dr. Robert Kratochvil, Associate Professor and Extension Specialist at the University of Maryland. “Through January, it was colder than normal resulting in a slow accumulation of Growing Degree Units. The first couple weeks of February were warmer and the number of Growing Degree Units increased. A further assessment conducted on February 16 combined with the extended forecast indicated that small grains would benefit from the first application of spring nitrogen on February 25.”
The University recommends split applications of spring nitrogen with the first application occurring on or soon after February 25 based on Growing Degree Units and the second application when the crops begin to joint.
For additional information on Maryland’s nutrient application requirements, contact the department’s Nutrient Management Program at 410-841-5959. Farmers with fields that are not suitable for harvest should contact their crop insurance agent for guidance.