Why do you worship Tulsi plant?
Worshiping Krishna’s devotees is an essential feature of devotion to Him. Sometimes great devotees appear in forms other than the human form. One such devotee, whose worship is central to the worship of Krishna, is Tulasi. She serves Krishna in the form of a plant, and devotees worship her in that form. Full of love for Krishna, she can give it to others.
Srimad-Bhagavatam (3.15.19) explains the special position of the Tulasi plant: “Although there are numerous flowering plants full of transcendental fragrance in the spiritual realm, they are aware that Tulasi is given special preference by the Lord, who garlands Himself with Tulasi leaves.”
In her form as a plant, Tulasi always stays at the Lord’s feet and around His neck. (Her leaves and flowers decorate His feet and are strung into garlands to be worn around His neck.) The Vedic scriptures say, “Krishna gives Himself to a devotee who offers Him merely a Tulasi leaf and a palmful of water.”
The wood of dead Tulasi plants is used to carve sacred beads devotees wear around their necks and use for chanting the Hare Krishna mantra.