Radhastami is the celebration day of Srimati Radharani's birth. Radharani is the consort of Krishna. She was born 15 days after Krishna's birth, which is celebrated also -Janmastami.
Traditionally, Followers of Gaudiya Vaisnavism will follow a half-day fast on this day. Radhastami Srimati Radharani is the eternal consort of Lord Krishna. Her appearance day is celebrated exactly two weeks after Krishna's.
Radharani's special qualification is that She is the best devotee of Krishna. Krishna therefore loves Her the most. On Her festival day, devotees seeking Krishna's grace will especially ask Her to grant them devotion to Her beloved Lord, knowing that if they can attain Her favour, they can attain His as a natural consequence.
Others may pray to Lord Krishna that He may permit them to approach the lotus feet of Srimati Radharani, knowing that if He is satisfied by their prayer then She will smile upon them also and pure devotion will be theirs.
Sri Sri Radha and Krishna are the Eternal Divine Couple and are forever bound up in transcendental love for one another. Worshipping Them is the goal of life for Gaudiya Vaisnavas. This esoteric subject matter is not openly discussed by devotees but on this special day devotees will remind themselves of the sublime goal of their religious practices.
On Radhastami, Sri Sri Radha Krishna deities are traditionally dressed entirely in flowers. A spectacular sight not to be missed! Also, please note that only on this day may you receive the auspicious darshan of Srimati Radharani's lotus feet. On all other days Her feet remain covered.
Devotees will fast until noon and sing devotional songs in praise of the Divine Couple and Their pastimes. Then a feast is served, most often including the famous Radha Red — a delicious, spicey, plum chutney.