As you pore over seed catalogs and do drive-by seedling snatches this spring, consider adding a new herb to your garden: holy basil (Ocimum sanctum, synonym O. tenuiflorum), which is also commonly called tulsi or sacred basil. This basil with benefits hails from India, where pots of the fragrant herb grace sacred temples. In the past decade or two, tulsi has infiltrated the American herbal lexicon and dietary supplement shelves, quickly becoming a favorite among herbalists and gardeners alike.
All species of basil offer anti-inflammatory, antioxidant, and digestion- and cognition-enhancing properties (who knew pesto could do all that?), but holy basil takes it a step further than common garden basils. Holy basil’s clove- and mint-like fragrance pulls people into a relaxing, Zen state. Most famously, tulsi acts as an adaptogenic herb, helping the body adapt to stress and find deep reserves of energy. Holy basil is the easiest of all adaptogens to grow and harvest in abundance, and its ability to both calm and energize makes it appropriate for almost anyone.
Holy basil specifically balances cortisol, a stress hormone that increases blood sugar. This benefit makes it useful as a hypoglycemic aid for people whose blood sugar and food cravings wobble with stress. Having holy basil with a meal or lightly sweetened with honey can help prevent hypoglycemia. That said, people taking medicine for diabetes or who are prone to hypoglycemia should monitor their holy basil intake closely and consult with a physician before making any big changes.
Holy basil is also considered a “great protector” and is used in India to fight respiratory infections and ulcers, as well as to protect against radiation damage and ease grief, mood issues, and depression.
Growing and Harvesting Tulsi
Grow tulsi as you would regular basil but with a little more pampering: full sun, rich soil with good drainage, and regular moisture. It will do best in warm-to-hot temperatures and growth will stall on cold nights. The plants will die when kissed by frost (no matter which type you grow), yet can be cranky in the greenhouse. Holy basil can be grown in pots but won’t tolerate being too dry or waterlogged. Treat tulsi as an annual.
Harvest the leaves and flowers often, and pinch back blossoms to encourage more vigorous growth. Where I live, in New Hampshire (Zone 4), I get three to four harvests from June through August of ‘Kapoor’ tulsi, which allows me to make a half gallon of tincture and to fill a gallon jar with dried, cut, and sifted herb from a dozen plants. Tulsi is a juicy herb that can take a week or longer to dry, and it loses a significant amount of volume in the process.
Species and Cultivars
As you begin to study and grow holy basil, you’ll realize that it isn’t actually just one plant but a constellation of plants with similar characteristics. To help make sense of the different types of tulsi, I contacted Noelle Fuller, a master’s candidate at the University of Georgia who has devoted the past few years to growing and studying the array of tulsi plants available. Most are types of Ocimum sanctum (synonym O. tenuiflorum) except for ‘Vana’ (O. gratissimum). All can be used interchangeably, though they can exhibit subtle differences.
‘Kapoor’ excels in temperate gardens with high yields and rapid growth. If your holy basil source doesn’t specify the cultivar, then it’s likely ‘Kapoor.’ In India, ‘Kapoor’ is weedy. It flowers profusely and is the most likely to self-seed. In spite of a lesser essential oil content than other cultivars, it has a bright flavor and potent aroma. The fact that you can get fresh and freshly dried ‘Kapoor’ makes it my favorite for personal and clinical use.
‘Krishna’ has purple stems and is the favored species in India for medicine, though it can take longer to grow and has lower yields. ‘Rama’ and ‘Amrita’ tend to be higher in essential oils, yet harder to germinate and grow. ‘Vana,’ a unique species that’s weedy in India, may be slower to grow, but it’s the most likely to survive as a tender perennial. ‘Vana’ is rich in clove-like eugenol essential oils.
“I don’t believe one cultivar is better than the others,” explains Fuller. “It depends on what you are doing, how the product is going to be used, and what you have available.” Her current favorite is a blend of ‘Kapoor’ and ‘Vana’ as tea. You can find a summary of Fuller’s tulsi research in this holy basil powerpoint presentation,which she assembled for the University of Georgia.
Holy basil marries well with a variety of herbal flavors. It’s generally best with leaves, flowers, and other herbs that you steep. Simmering (decocting) tulsi will evaporate many of its benefits. If you want to blend it with roots (such as ashwagandha) that generally require an extended amount of simmering, then consider blending the herbs in a tincture or infusing them in a warm thermos, which will extract the properties from the roots without damaging the more fragile tulsi leaves. Feel free to experiment with the herbs you have on hand; holy basil does a nice job perking up the flavor of bland herbs.
• Tulsi and lemon balm (fresh or dry): Boosts relaxation, digestion, and cognition.
• Tulsi and rose (fresh or dry): Gladdens the heart; eases grief; relieves stress.
• Tulsi and green tea (dry): Boosts energy, mood, and cognition; decreases inflammation; curbs cravings; eases stress.
• Tulsi and elderberries (dry): Supports immune function; rich in antioxidants.
• Tulsi and peppermint or chocolate mint (fresh or dry): Boosts digestion, cognition, and mood.
How to Enjoy and Preserve Tulsi
While you could cook with holy basil, it’s much tastier as a tea and in various herbal preparations. It’s equally useful fresh or dry, but store-bought dried holy basil can be lackluster in quality and flavor. Opt for homegrown or recently harvested holy basil from herb farms that grow their own. Try a low dose first, then work your way up to find the best dose for you.
• Hot tea (fresh or dry): Steep 1 teaspoon dry herb (or 2 teaspoons fresh) in 1 cup of hot water for 5 minutes or longer. Holy basil can steep for minutes or hours without tasting bitter. Strain and drink 1 to 4 cups daily.
• Iced tea (fresh or dry): Either refrigerate a hot tea until cold or brew a double-strength hot tea (2 teaspoons dry herb or 4 teaspoons fresh herb per cup). Steep for at least 5 minutes, and then pour over ice. Strain and drink 1 to 4 refreshing cups daily.
• Infused water (fresh): Cover a few sprigs of fresh herb with cold or room-temperature water, and then let steep at least 5 minutes or up to 1 day. Strain and drink 1 to 4 cups daily.
• Herbal seltzer (fresh): Follow the infused water directions above using club soda or plain seltzer. After straining, sweeten with simple syrup, honey, or stevia to taste (if desired). Drink 1 to 4 cups daily.
• Tincture (best fresh): Tightly pack a glass jar with as much coarsely chopped, fresh holy basil leaves as you can. Cover completely with vodka or brandy that’s at least 80 proof. If the materials condense, top off the jar with more of the same alcohol a few days later. Strain the herbs after 1 month, squeezing out as much liquid as possible. Bottle, label, and store in a cool, dark spot for 5 to 10 years. Take 1 to 2 milliliters as needed, up to 6 times per day (1 mL is equivalent to 1 full squirt from a tincture bottle dropper).
• Oxymel (best fresh): Follow the instructions for making a tincture, but instead of alcohol, cover your herbs with a blend of honey and apple cider vinegar (1-to-2 or 1-to-1 depending on how sweet you want it). Cover with a plastic lid (vinegar eats metal) and strain after 2 to 4 weeks. Oxymels will keep for about 6 months and are best kept refrigerated. Take 1 teaspoon to 1 tablespoon as needed.
• Infused honey (best fresh): In a stockpot, cover 1/2 cup of loosely packed, chopped holy basil leaves with 2 cups of honey. Gently bring to a simmer, stirring frequently. Remove from heat before it boils. Repeat this process 2 more times, then strain on the last heating. Infused honey should be shelf-stable for 6 to 12 months. Enjoy by the spoonful as desired.
• Glycerite (best fresh): Glycerites are similar to tinctures and are a good option for children or those wishing to avoid alcohol. Firmly fill a canning jar 3/4 of the way with chopped herb, and then cover with vegetable glycerin and distilled water (3-to-2), leaving about 1 inch of headspace. Screw on a canning lid, set the jar into a stock pot, cover with water, and simmer for 20 minutes. Let cool and then strain. Glycerites should be shelf-stable for at least 1 year. Take 2 to 4 mL as needed.
• Capsules (dry): Grind your dry herb into a powder. If desired, sift this through a very fine metal strainer to get an even finer powder. Using your hands or a capsule machine, fill empty capsules. Take 500 to 1,000 milligrams 1 to 3 times daily. (Size “0” capsules hold approximately 500 mg.)
• Hydrosol (best fresh): Harvest a basket full of fresh holy basil. In a large stock pot, cover the herb with a few inches of water. Place an empty, sturdy, heat-safe bowl in the middle (place it on a clean brick if needed to keep it from floating around). Cover with the lid upside down so the condensation can collect and drip back into the bowl. Simmer for a few hours, collecting the distilled water and essential oil in the bowl. Use 1 teaspoon in recipes or as a light aromatherapy spray.
When searching for holy basil, keep in mind its various common names (tulsi, holy basil, and sacred basil), along with its Latin names (Ocimum sanctum, O. tenuiflorum, and O. gratissimum). Some producers will specify the cultivar, but if they don't, then you can assume it's 'Kapoor,' the most widely available and easiest to grow.
Strictly Medicinal Seeds offers a nice selection of holy basil seeds.
The following companies carry unspecified cultivars that are most likely 'Kapoor.'
Ask for seedlings at your local nurseries or garden centers, especially those that specialize in unique herbs. If they don't sell holy basil already, ask whether they would consider growing and selling it. Be aware that the 'Kapoor' cultivar is usually the most productive in the garden, but that all holy basils can be finicky to grow from seed.
Fresh Holy Basil
Dry Holy Basil
Maria Noël Groves is a registered clinical herbalist whose home is nestled in the pine forests of New Hampshire. She’s the author of Body into Balance: An Herbal Guide to Holistic Self-Care. For herbal recipes, information about the book, long-distance consults, and online classes, visit Wintergreen Botanicals.