It is celebrated 8 May, the anniversary of the death of Helena Petrovna Blavatsky, founder of the Theosophical Society.
The lotus is born under the mud, growing through the water to achieve the surface, and therefore the air and the light of sun.
This growth is identified with man's life, born in earth but desiring the elevation to the air; representing his middle stage between animals and the ultimate reality.
The seeds of lotus contain (even before they germinate) perfectly formed leaves, a miniature shape of what they would become.
In her will, HPB suggested that her friends might gather together on the anniversary of her death (May 8, 1891) and read from Sir Edwin Arnold's The Light of Asia and from The Bhagavad Gita.