Many burley growers follow the practice of applying 1-2 gallons/A of liquid fertilizer to their tobacco crop by mixing it with their sucker control chemical and spraying the combined mixture on the crop soon after topping. This practice is thought to improve yields. However, previously reported testing of this practice by the University of Kentucky College of Agriculture indicated that it did not improve yields.
Wells, Kenneth L. and Strohmeier, Kim D., "Foliar Fertilization of Burley Tobacco at Topping" (1989). Soil Science News and Views. 141.