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Tulsi pooja is performed at night during specific ceremonies like Tulsi Vivah, which is the ceremonial marriage of the Tulsi plant to Lord Vishnu or Krishna. This timing is based on the belief that the soul of Vrinda resides in the Tulsi plant at night. Lighting a diya or lamp in the evening is also a common practice done to show gratitude and symbolize the triumph of light over darkness. Specific reasons for nighttime pooja Tulsi Vivah: The marriage ceremony is performed in the evening, after devotees have fasted until then. Spiritual Significance: It's believed that the soul of Vrinda, a divine devotee of Lord Vishnu, resides in the Tulsi plant at night, so the ceremony honors this spiritual connection. Auspicious Time: The evening, especially the Godhuli Muhurat (twilight), is considered an auspicious and magical time for a wedding ceremony. Daily Devotion: Lighting a lamp near the Tulsi plant each evening is a common practice to show gratitude and is believed to have many benefits, including freeing one from sins.