Potatoes (Solanum tuberosum) are an important high-value commodity for producers in the Mid-Atlantic Region. Current production recommendations were based on white potatoes, and practices for Russet potatoes have not been researched in this region. The objective of this study was to test impacts of N rate (0, 67, 134, 201, and 268？kg？N？ha？1), N application timing (100% applied with planter, 2-way split (30% with planter and 70% band applied approximately 30 days after planting at dragoff), and three-way split (30% with planter, 50% band applied prior to drag-off, and 20% band applied at first sight of bloom)), and additions of the growth regulator maleic hydrazide (MH-30). We tested “Goldrush” and “Norkotah” Russet potato varieties on marketability, total yield, tuber deformity, and tuber soft rot incidence for sandy loam soils in the Mid-Atlantic. Overall, year variations were significant with substantial rots (up to 86.5%) occurring in year 3. Maleic hydrazide and N application timing had little consistent effect on any tested parameter. Nitrogen rate and variety factors had the greatest impacts on deformity, tuber rots, and yields for Russet potatoes in the Mid-Atlantic Region with 134？kg？N？ha？1 producing the highest total yields in 2009 and 2010. If tuber rots can be controlled, both “Goldrush” and “Norkotah” are acceptable varieties under the Mid-Atlantic production practices. 1. Introduction Potatoes are an important crop to Virginia and the rest of the Mid-Atlantic Region that includes Delaware and Maryland, USA. Annually, the Mid-Atlantic states produce 4049 hectares (ha) of potatoes with an average yield of 30,091？kg tubers ha？1 worth $9.97 million (5 year averages) [1]. Sandy loam soils in the Mid-Atlantic Region are favorable for potato production. However, a close proximity to sensitive water bodies, such as the Chesapeake Bay, means that fertilizer use efficiency and reduction of nutrient losses from production fields are more important than ever before. Intensive fertilizer management is necessary in sandy loam soils in the Mid-Atlantic to ensure proper nutrient supplies to growing crops. Sandy loam soils generally have overall low organic matter, low cation exchange capacities, and low total nitrogen (N) in the upper horizon, which means that little N is mineralized from soil organic N sources and N must be applied with fertilizer to match crop uptake needs [2]. For instance, Stanford and Smith [2] found that a Norfolk fine sandy loam had little initial N mineralized after 4 weeks of incubation (7.3？mg？kg？1) and this amount gradually fell
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