What is Onam?
Onam is Kerala’s harvest festival and the homecoming of Mahabali, the king whose reign is remembered as the age when everyone was equal. It is dated by neither a tithi nor a sankranti but by a nakshatra — the day the Moon stands in Thiruvonam during Chingam, the first month of the Malayalam year — which is why it can fall anywhere from mid-August to mid-September.
How it is observed
The ten days run from Atham to Thiruvonam, with a pookalam — a carpet of flowers — laid at the doorway each morning, a ring wider than the day before. Thiruvonam itself is the Onasadya: two dozen or so vegetarian dishes served on a banana leaf and eaten by hand, payasam last. The vallam kali boat races and the Pulikali tiger dance belong to the same week.