Holy basil doesn’t make your pesto divine. It isn’t even the same species of sweet basil used in your favorite Italian dishes. Holy Basil, also known as Tulsi, can be two different herbs, Ocimum gratissimum, or Ocimum tenuiflorum. It is a member of the mint family (Lamiaceae). The wonder herb holy basil, often called “The Queen of Herbs”, is native to Southeast Asia and is commonly used in Ayurveda (traditional medicine in India) to make healing teas, oils, and poultices.
Easily propagated by seed or a cutting, holy basil is grown as an annual in most of the United States, but it will grow as a perennial in warmer climates and can even do well as an indoor plant in the right conditions. Even those who have no interest in its medicinal and culinary uses plant this lovely herb for its attractive foliage, flowers, and alluring aroma.
Whether growing holy basil for medicinal, spiritual, culinary, or aesthetic purposes, this herb will be a beautiful and satisfying addition to your garden or your houseplant collection.
|Botanical Name||Ocimum tenuiflorum, Ocimum gratissimum|
|Common Name||Holy Basil, Tulsi, Tulasi|
|Plant Type||Herbaceous shrub|
|Mature Size||Two feet tall and one to two feet wide|
|Sun Exposure||Full Sun|
|Soil Type||Moist, sandy loams with good drainage|
|Flower Color||Purple or white|
|Hardiness Zones||10b to 11, USDA|
|Native Area||Indian Sub-Continent, Southeast Asia|
Holy Basil Care
Growing holy basil is an easy endeavor, regardless if you grow it from seed, cuttings, or transplant seedlings. The most challenging thing you will encounter might be obtaining plants, so propagating from seed is usually the best bet. If you do happen to find holy basil for sale, be sure you have the correct species. When selecting plants, knowing the difference between Thai basil (O. basilicum var. thyrsiflora) and holy basil, sometimes called Thai holy basil, will determine if you make a healing tea or one that tastes like pesto.
Holy Basil can grow directly in your garden or a container both indoors, as a houseplant, or outdoors in the garden that be brought indoors to overwinter. Either way, the methods of caring for both are similar.
Giving holy basil plenty of sunlight will ensure large healthy leaves. This plant will tolerate some shade, but anything more than dappled shade and you will notice a decline.
Though holy basil does grow quite well in most soils, it takes minimal effort to thrive. The ideal soil type is light and airy but rich at the same time. A silty loam is a good choice because it retains some moisture but drains well. Soaking wet soil is problematic, so if soil drainage is an issue, you can amend the soil with perlite to promote drainage.
Keeping the soil moist but not drenched and soggy is the key to growing healthy and abundant holy basil. This rule applies to growing the plant indoors or outdoors.
Another consideration when watering basil is a disease; basil downy mildew is often spread by infected soil being splashed up on the leaves. Soaker hoses or drip irrigation systems can prevent fungal spores from splashing up from the soil.
Temperature and Humidity
Holy basil’s native range is located in a tropical region, so maintaining an average temperature of 70 degrees Fahrenheit is necessary if you want the plant to survive outdoors. If your local temperature is above this year-round, holy basil will act as a perennial.
In cooler hardiness zones, this plant will be annual unless you plant it in a container and move it indoors in the colder months. The USDA recommends holy basil will do well in USDA zones 10b to 11, but you can grow it indoors in any zone.
When you fertilize an herb, foliage grows quickly in response to the fertilizer and profuse flowering occurs. Usually, this result would be welcomed on most other flowering plants but what happens with herbs is that the herb's essential oils are not as concentrated, and the result is very weak flavor. Inducing early flowering means energy is spent on blooms and not on foliage, and again, the foliage is, for the most part, where the flavor is. So it's best to skip the fertilizer.
Holy Basil Varieties
- Rama tulsi has a cool flavor known for its mellowing effects. Rama has green foliage, purple blossoms, and a green or purple stem, depending on the season.
- Krishna tulsi tastes similar to black pepper and is known for its high medicinal value. Krishna holy basil is dark green with violet stems, foliage, and light purple blossoms. It grows in the meadows of the Indian Sub-Continent and has been successfully cultivated for private gardens and use in temples.
- Kapoor tulsi the most widely cultivated variety you will find in the United States. It is a shorter-growing annual variety that bolts quickly with profuse flowers and a mild flavor compared to other varieties. Due to the number of flowers, this variety is an excellent food source for pollinators but the least attractive for medicinal uses. If planning to bring your plant indoors, seek out one of the other varieties.
- Amrita tulsi is the least commonly grown. Amarita tulsi means immortality, and that is fitting for this plant. It is a perennial that is nearly indestructible and simple to grow. If you plan to grow holy basil in a container, this is the variety to select.
- Vana tulsi is actually the species O. gratissimum. The very tall variety is incredibly aromatic with a strong clove scent . Vana has green leaves and stems with white blossoms. It is used mostly for medicinal purposes.
Propagating Holy Basil
To start holy basil from seed, do so indoors four to six weeks before the first frost. Sow seeds in a good quality seed starting mix. Using a heat mat will increase the speed and germination rate. Placing a fan to circulate air over the seedlings will produce stronger plants.
Propagating holy basil from cuttings is an easy task. Use a pair of sharp sanitized snips or a sharp grafting knife and make an angled cut about six inches long just below a leaf node. Remove the lower leaves from the cutting and place the cutting in water, changing the water frequently. Wait till roots develop and then transplant into good quality potting soil.