The month of May is dedicated to the Blessed Virgin Mother Mary. For us Catholics, during the entire month of May, it is customary to commemorate Mother Mary with special devotions every day.
The derivation goes back to the ending of 13th century. In the 16th century it became a norm as it appeared in various manuscripts and literature. Mother Mary, Mother of our Lord and Saviour Jesus Christ, is known for her deep humility, blind obedience, ardent love, heroic patience, and angelic kindness.
During the month of May, we can make an extra effort to include these virtues into our everyday lives to remind ourselves of our Mother.