Holy basil (Ocimum tenuiflorum or Ocimum sanctum), also known as tulsi, is considered to be sacred and devout Hindu women around the world include the plant in their morning rituals. As the legend is told, a woman named Tulasi was tricked into betraying her husband when the god Vishnu appeared as her husband and seduced her. In utter misery, Tulasi killed herself. After her death Vishnu declared that she would be worshipped for her faithfulness, and the plant has become a symbol of love, eternal life, purification and protection.
A perennial in the tropics, holy basil can be grown as an annual or kept alive over the winter in a sunny window or greenhouse. We recommend that you transplant the plant when it arrives into a larger pot (at least one gallon) using premium potting soil. Keep it damp but not wet until it starts showing new growth. Use a balanced fertilizer and follow directions exactly.
It prefers at least three hours of sun a day, and will tolerate even more if soil is kept uniformly damp. This is krishna tulsi; the leaves are a darker purple and tastier the more sun it receives. It can grow as high as five feet tall over a period of two or three years in a five- to seven-gallon pot.
We see an occasional snail or slug on the tulsi if it is damp in the greenhouse, but our biggest problem over the years has been spider mites. These are tiny creatures, almost invisible to the naked eye, that live on the underside of the leaf and suck juices from the plant, leaving tiny white spots in the leaf. They spin webs from leaf to leaf, but the plant is very infested by the time the webs become visible. The best way to treat spider mites is to prevent them. They thrive in hot dry conditions, so keep the soil wet. If you catch an infestation early, spray water underneath the leaves daily to disrupt their life cycle. If the problem is more severe, neem oil or cake also can be used.
As you would expect from a holy plant, tulsi is used extensively in Ayurveda. Modern research supports these traditional uses, noting that it contains powerful antioxidants. Although stronger than most green basils, it can easily be exchanged in any recipe. It also can be eaten straight from the plant or used to make a very tasty tea. As always, avoid using any herb if you are pregnant, breast-feeding, or trying to conceive without the specific advice of a healthcare professional.