Castile was released by the USDA and the New York State Agriculture Experiment Station in 1991. The vine maturity of Castile is main season. Plants are medium to large, initially upright and later spreading and dense.
Stems are green with slight purple pigmentation mostly at the nodes.
Wings are prominent, straight to slightly waved. Leaves are medium to dark green with four pairs of primary leaflets. Flowers are violet with white tips. Tubers are oblong, slightly flattened with shallow eyes. Skin is smooth and white.