Sacred basil is a basil cultivar native to India, where it is used extensively in Ayurvedic medicine for a range of health complaints. In India, sacred basil is regarded as a sacred or holy plant, and it is widely cultivated around Indian homes. In addition to being used in India, sacred basil also appears in other Southeast Asian cultures, where it is utilized in cuisine and in traditional folk medicine. It can also be grown alongside Mediterranean basil, also known as sweet or European basil.
The scientific epithet for sacred basil is Ocinum sanctum. It is also known as holy basil, Thai basil, or tulsi. This annual plant grows to roughly knee-height, with thick stalks and purple-tinged serrated leaves. The flowers are white to red in color, with some plants producing almost purple flowers. Like other basils, sacred basil has a rich aroma which rises whenever the plant is brushed against or crushed.
In cuisine, the leaves and the seeds of sacred basil can both be used. Fresh leaves are often used to add zest and flavor to a range of dishes, including curries, and the seeds are used in spice mixtures across Southeast Asia. The seeds also contribute slightly to the thickening of watery and thin sauces, and are often used to bulk up sauces in Thailand. Leaves and seeds can be eaten raw and fresh, dried, or cooked, and some people enjoy chewing the stalks as a breath freshener.
This plant grows in tropical to semitropical climates, preferring spots with lots of sun and soil which have been well-amended with compost or fertilizer and sheltered from the wind. Sacred basil has moderate water requirements, preferring soil which is moist, but not wet, and it is important to avoid splashing water on the leaves. If the leaves get wet, they will burn and shrivel.
Gardeners who grow sacred basil can trim leaves off as needed, although no more than 30% of the leaves should be removed at any given time if the plant is to survive. In its native climate, sacred basil will die off slightly during the winter months, but re-emerge in the spring. Cold climates generally kill the plant off in the fall and winter, so it is a good idea to save seeds in cooler regions of the world for the purpose of cultivating sacred basil in the following year.
When selecting sacred basil in the market, cooks should look for crisp leaves with no soft spots or areas of molds. The basil will keep best if it is lightly covered in plastic and placed in a cup of water under refrigeration.