Research conducted in Maine using full season high glucosinolate mustard (HGM) cover crops have shown success at reducing the incidence of black scurf (Rhizoctonia solani) and occasionally scab (Streptomyces scabies). Commercial potato growers have been less than enthusiast about giving up production land to cover crops that do not provide regular income. In 2011 and 2012, experiments were conducted to evaluate HGM cover crops planted following the harvest of a marketable crop. Planting dates ranged from August 1 to September 15. Yield of HGM was significantly influenced by planting date and variety. Effect on potato skin quality will be presented.