Nandotsav which is also known as Nanda Mahotsav is celebrated on the next day of Krishna Janmashtami. Nandotsav is celebrated in most of the Krishna temples in Mathura and Vrindavan. In 2013, the date of Nandotsav is August 29.
The word Nandotsav is formed after joining of Nanda and Mahotsav. Nanda refers to foster father of Lord Krishna and Mahotsav refers to celebrations. Hence the event refers to celebrations held at Nandgaon to mark the arrival of Lord Krishna.
Nandotsav is also referred as Dadhi-Kando (दधिकांदौ). Dadhi-Kando is a mixture of curd and milk which is colored with Haldi, Chandan and Kesar known as turmeric, sandal and saffron respectively. In Dadhi-Kando, Dadhi refers to the curd and Kando refers to the sludge.
Dadhi Kando is thrown on devotees during Nandotsav celebrations. Devotees who are sprinkled or smeared by Dadhi Kando are considered lucky as it is believed to be “Lala ki Chhee Chee” i.e. potty of new born Krishna.