Tulasi is one of the most sacred plants in India, and many worship this plant daily as a means of cultivating their own consciousness through the power of devotion. Tulasi gives Sattwa, or positivity and healing power. It is said to open the heart and mind, increase the sense of spiritual love, and to enhance devotion, faith, compassion and clarity. It also helps to develop pure awareness. Tulasi helps to enhance the quality of Rasa Dhatu (nutrient plasma), Rakta Dhatu (blood), Majja Dhatu (bone marrow and nerves) as well as Shukra Dhatu (reproductive fluids).The foliage is green or purple, strongly scented. Leaves have petioles and are ovate, up to 5cm long, usually somewhat toothed. Flowers are white, tinged purple, borne in racemes
In India, one plant is universally appreciated by yogis, mystics and saints of the many and varied spiritual traditions. The botanical name, Ocimum sanctum, (sanctum meaning holy), is used out of respect for an ancient tradition that has a written history of over 5000 years. There are numerous references to this sacred plant throughout the Vedas, verified as the oldest texts in existence.The flowers, leaves and wood are an integral part of Indian life and worship. No temple offering is considered complete without Tulasi leaves or flowers, and the wood is carefully carved for wearing and as neck beads and japa mala, meditation beads used for counting mantras and prayers.Her qualities and amazing powers are found throughout the oldest writings on earth, the Sanskrit Vedas of ancient India, where it states that simply touching the wood is purifying at many levels
Tulasi is understood to be the plant incarnation of Vrindadevi, the archetypal "forest goddess". She beautifies the flora and fauna of the ultimate spiritual forest, Vrindavana. 
.She appears in this world so that her leaves may be used in the worship of Krishna, the God of love.A garland of tulasi leaves is the first offering to the Lord as part of the daily ritual. Tulsi is accorded the sixth place among the eight objects of worship in the ritual of the consecration of the kalasha, the container of holy water.
Followers of Hindu traditions often keep a Tulsi plant in front of their house. On a specific day each year known as 'Kartik Shukla Dwadashi' (usually about two weeks after Diwali) there is a tradition wherein Tulasi plants will be beautifully decorated with structures made of sugarcane, mango leaves and flowers and then a puja (form of worship) is offered.
As with Diwali celebrations there are usually clay lamps lit around the Tulasi plant and the house. In some parts of India people will have also have fireworks displays to mark the occasion. In northern India and in Gaudiya Vaishnava communities it is called the 'Tulsi vivah' or the wedding day of Tulasi with Krishna in his Sila form. There is another celebration called Tulsi Ekadashi where Tulasi is worshipped on the Ekadasi day.
Tulasi plants are prized in Ayurveda, where they are an integral part of that sophisticated healing system. Western chemists also recognize the considerable healing potential of Tulasi, which belongs to the same family as basil, and have isolated eugenol, carvacrol, methyl eugenol and caryophyllene from the leaves alone. Rama Tulasi, Shyama or Krishna Tulasi and Vana Tulasi are the 3 types that are available. All the three have amazing medicinal properties. It has antioxidant properties that help the body fight off damaging free radicals that have been related to disease and aging. It also is an effective adaptogen that helps the body fight off the stress, nervous breakdowns etc.It's anti inflammatory nature helps protect the entire respiratory system. Not only does it help purify the atmosphere, it also protects the skin as it is rich in Vitamin C. It also has good uses to solve ailments related to digestion.