01What Holika Dahan is
Holika Dahan is the bonfire lit on the Purnima of Phalguna, the full moon at the end of winter, on the night before Holi. In the north it is also called Chhoti Holi; in parts of the south the same night is Kama Dahanam. Neighbourhoods gather wood and cow-dung cakes for days beforehand, and the fire is lit at the muhurat the panchang gives, after Bhadra is over.
02The story told of it
The Bhagavata Purana tells of Prahlada, a boy devoted to Vishnu, whose father Hiranyakashipu, king of the asuras, demanded to be worshipped himself. When threats failed, the king's sister Holika, who was said to be shielded from fire, sat in a burning pyre with Prahlada on her lap. The boy came out unharmed, and the shield Holika relied on failed her. The bonfire remembers that night, and the tradition reads it as devotion outlasting pride.
03How it is kept
In the afternoon women worship the stacked pyre, wind raw cotton thread round it three or seven times and offer water, roli, rice, flowers, coconut and new grain. At the muhurat the fire is lit, families walk round it, and ears of new wheat and barley, gram and sugarcane are roasted in it and shared as prasad. Many carry home an ember or ash from the fire, and the next morning is Holi, the festival of colours.
04How the day is chosen
Holika Dahan is kept in Pradosh, the evening after sunset, on the day Purnima first covers it, and away from Bhadra, the half-tithi the tradition asks to avoid. When Bhadra lasts past midnight the tradition allows the fire in Pradosh, or in Bhadra Punchha, its tail, but never in Bhadra Mukha; when Purnima also runs through nearly the whole of the next day, the fire moves to that evening.
05Holika Dahan in other years