Tulsi is an upright bushy shrub that grows up to 18 inches. It's hairy stems sprout oval leaves with serrated edges, and depending on the variety, range in color from light green to dark purple. The tulsi plant blooms erect purple or reddish flowers and produces tiny rust-colored fruit. It has a strong, pungent aroma and taste that is similar to other varieties of basil.
Tulsi is a hardy annual but can grow as a perennial if the flowers are cut before blooming. Sow tulsi seeds after the last frost in a well-drained, fertile, lightweight soil and cover with a thin layer of soil. Allow tusli to receive at least four hours of sunlight and protect from harsh afternoon sun and high heat. Water the holy basil thoroughly and allow to dry out between waterings. Use a balanced, water-soluble fertilizer during the active growing period and discontinue during the cooler months when the tulsi plant goes dormant.
Several varieties of holy basil grow throughout the Himalayan foothills to areas of the Middle East. Purple-leafed tulsi, also known as Krishna or Shyama tulsi, has a sharp peppery taste and is harder to find than other varieties. Rama tulsi, or green leaf tulsi, has a mild taste with a strong aroma. It's found in southern areas of India and in some parts of China and Nepal. Wild tulsi, or Vana tulsi, grows wild around the Himalayan Mountains and in the plains of India.
Holy basil contains essential oils that work as an adaptogen, which aids the body in adapting to stress, as well as an antidepressant. Tulsi's constituents are also antibacterial and antifungal and work as a diuretic. Holy basil is believed to help strengthen the immune system and can help reduce the signs of aging by regulating stress, increasing immunity and eliminating free radicals. Additionally, tulsi leaves provide a range of nutrients including vitamins A and C, calcium, zinc, iron and chlorophyll.