Kason Watering of the scared Bo Tree Festival:

Kason(May), the second month in the Myanmar calendar, is deemed the hottest month of the hot season. Yet it is the most significant day in the Buddhist world. The full moon day of Kason is deeply intertwined with the milestones in the Buddhas life. It is a day four times blessed. To Myanmars it is the festival of pouring water on the Bodhi tree. This day is called Vesak Day in other Buddhist countries.

The full moon day of Kason is the Buddha Day, celebrated by the Buddhist faithful throughout the world. On this day Dipankara Buddha prophesied to the hermit Sumedha that he would become Gotama Buddha, the latest one in this Baddha World, who again on suchlike days was born, attained Enlightenment(i.e, became the Buddha), and entered Parinibbana(i.e, passed away).

The Bodhi tree(Ficus Religiosa), under which former prince Siddhattha attained Enlightenment, is held sacred. Hence the act of pouring water on it is an expressiion of piety and respect shown to him. The Kason-water pouring ceremony is usually preceded by a brilliant pageantry. Participants come carrying pots of water and Eugenia springs and flowers. Then chanting of Paritta verses, a brief explanation of the rites, recitation of poems praising the Lord Buddha. Finally, water is poured at the foot of the Bodhi tree. Yet festive atmosphere is not lacking: light refreshments are served accompanied by music and dance performed by amateur merry-makers.

Every pagoda in Myanmar worth its salt has a sacred site complete with a Bodhi tree in its precincts. You can watch grander Kason ceremonies at all the bigger pagodas including the Shwedagon Pagoda.