Tulasi Kalyanam / Tulasi Vivaaham, Thulasi Thirumanam
Tulsi means Holy Basil. Vivah means marriage. Here, The Tulsi weds the Hindu god Vishnu or his avatar Krishna .
The tulsi plant is held sacred by the Hindus as it is regarded as an incarnation of Mahalakshmi / Mahalaxmi, born as Vrinda (Brinda).
She is often called as Vishnupriya, the beloved of Vishnu
The Tulsi wedding signifies the end of the monsoon and the beginning of the Hindu wedding season.
As per Hindu mythology, Vrinda (Tulsi) was married to demon king Jalandhar. He was the king of oceans and had immense powers. Demon Jalandar harassed all. Due to the effect of prayer of Tulsi, he became invincible, and no god was able to harm him. However Jalandhar was killed by Lord Shiva and Lord Vishnu took the form of Jalandhar and stayed with Tulsi. Vrinda crused Vishnu and turned Him into a special auspicious stone called Shaligram and then burnt herself on her husband's funeral pyre. The Tulsi plant came into existence from her body. (Tulsi leaves are essential for Vishnu pooja / puja). Lord Vishnu declared that those who perform the sacred marriage of Tulsi with Him (Vishnu) will get great merits and devotion. Tulsi vivah is being celebrated in different days in different parts of India , but usually on Prabodhini Ekadashi. It is an important ritual observed in the month of Kartik (October – November).On this wedding day, tulsi is married to Shaligram.
The marriage of Tulsi with Lord Maha Vishnu resembles the traditional Hindu wedding. Vrindavan (Tulsivan) is coloured and decorated as a bride. Sugarcane, branches of tamarind tree and that of gooseberry (amla) are kept near the tulsi plant. Various vegetarian food are offered to Tulsi Vrindavan and Lord Maha Vishnu and the Prasadam (Prasad) is distributed to all.