Saint Joseph's Day takes place on March 19, 2018. Saint Joseph's Day, the Feast of St. Joseph is in Western Christianity the principal feast day of Saint Joseph, Spouse of the Blessed Virgin Mary. It has the rank of a solemnity in the Roman Catholic Church; Catholics who follow the Missal of 1962 celebrate it as a first class feast.
March 19 always falls during Lent, and traditionally it is a day of abstinence. This explains the custom of St. Joseph tables being covered with meatless dishes. If the feast day falls on a Sunday other than Palm Sunday, it is observed on the next available day, usually Monday, March 20, unless another solemnity falls on that day. Since 2008, if St Joseph's Day falls during Holy Week, it is moved to closest possible day before 19 March, usually the Saturday before Holy Week. (With material from: Wikipedia)