Chaturmas runs from Devshayani Ekadashi in Ashadha to Prabodhini (Dev Uthani) Ekadashi in Kartika. Tradition holds that Vishnu rests in yogic sleep during these months.
It is a time for vows, study and simpler living. Many avoid weddings and griha pravesh until it ends, which is why the wedding season begins after Dev Uthani Ekadashi.
Monastic traditions often stay in one place for the season.
