Rhizoctonia solani is the most damaging pathogen on sugarbeet (Beta vulgaris L.) in North Dakota and Minnesota. Research was conducted to evaluate penthiopyrad for controlling R. solani and determine when the plants are most susceptible to infection. Penthiopyrad applied in-furrow and as a soil drench resulted in significantly higher percent survival than the positive control whereas penthiopyrad applied in a band was ineffective at controlling R. solani. Penthiopyrad can also be used as a seed treatment at the 14 g rate to provide effective control of R. solani. Sugarbeet plants, irrespective of their inherent level of resistance, were easily infected by R. solani up to three weeks after planting, even longer for susceptible varieties, highlighting the need for additional protection in the form of seed treatment or fungicide application that may be required to protect vulnerable sugar beet planted in fields with a history of the disease.