The Carmelite Order has had a particular devotion to St. Joseph for many centuries, venerating him with the title "Principal Protector of the Carmelite Order". Since Joseph cared for Mary and for Christ in a particular way, we believe that he also cares for the Carmelite Order which is devoted to Mary and Christ.
For more information on the significance of St Joseph in the liturgical calendar see the link below:
https://www.carmelite.org/carmelite-spirituality/saints-of-carmel/st-joseph