Thai basil is a Southeast Asian herb with a licorice and anise flavor, distinct from Italian sweet basil
Thai basil is a leafy herb native to Southeast Asia with a flavor profile that sets it apart from the basil most Western cooks know. Where Italian sweet basil tastes mild and slightly peppery, Thai basil carries strong notes of licorice, anise, and clove — a flavor closer to fennel than to garden basil. The plant itself looks different too: the leaves are narrower and more pointed, the stems often have a purple tint, and the flowers are small and clustered rather than loose and open.
In Thai cuisine, Thai basil appears in curries, stir-fries, and soups, where its bold flavor holds up against heat, fish sauce, and chili. It is added at the end of cooking or used raw as a garnish, because the flavor fades if simmered for long. You will find it in dishes like pad krapow moo (pork with basil) and green curry, where it is a core ingredient rather than a supporting note.
Key Takeaways
- Thai basil has a licorice and anise flavor that is much stronger than Italian sweet basil and does not taste like a direct substitute.
- The plant has narrower, more pointed leaves and often purple-tinged stems, making it visually distinct from sweet basil at the market or in a garden.
- Thai basil loses flavor quickly when cooked for long periods, so it is typically added near the end of cooking or used as a fresh garnish.
- Three main varieties — Thai sweet basil, Thai holy basil, and lemon basil — are used in different Thai dishes and have their own flavor profiles.
How Thai basil tastes compared to sweet basil and other herbs
Thai basil and Italian sweet basil come from the same plant family but taste nothing alike. Sweet basil is mild, slightly peppery, and works well in tomato sauces and pesto. Thai basil is assertive: the licorice and anise notes dominate, followed by hints of clove and a peppery finish. If you substitute sweet basil for Thai basil in a curry, the dish will taste flat and incomplete. If you use Thai basil in a tomato sauce meant for sweet basil, the flavor will clash.
Thai basil is also different from holy basil (also called tulsi), which is used in some Thai dishes but has a sharper, more medicinal taste with less sweetness. Lemon basil, another Southeast Asian variety, carries citrus notes instead of licorice. In a Thai restaurant kitchen, these are three separate ingredients for three different purposes, not interchangeable options.
Where to find Thai basil and how to store it
Thai basil is sold at Asian grocery stores, farmers markets, and some mainstream supermarkets with strong produce sections. It is often labeled as "Thai basil," "sweet basil," or sometimes "Asian basil" — the label depends on the seller. At a farmers market, ask the grower directly if you are unsure. The plant should have firm stems, no wilting, and leaves that are bright green or green with purple tinges.
Fresh Thai basil keeps for three to five days in the refrigerator if stored correctly. Wrap the stems loosely in a damp paper towel, place them in a plastic bag, and refrigerate. Do not wash it until you are ready to use it — moisture speeds decay. For longer storage, you can freeze Thai basil in ice cube trays with a little water or oil, though the texture will soften and it works best in cooked dishes after freezing.
How Thai basil is used in Thai cooking
Thai basil appears in three main ways in Thai cuisine. First, it is added to hot dishes — curries, stir-fries, and soups — in the last minute of cooking or after the heat is off. The heat releases the oils and flavor without cooking them away. Second, it is used as a raw garnish on finished dishes, where the full licorice and anise notes come through. Third, it is sometimes bruised or torn and steeped in hot liquid to infuse flavor into a broth or sauce.
Pad krapow moo (minced pork with Thai basil) is perhaps the most recognizable dish: the basil is added to the pan at the very end, wilts slightly, and the whole dish is served over rice with a fried egg. In green curry, Thai basil goes in after the curry simmers, so it softens but does not disappear into the sauce. The timing matters because Thai basil's flavor is volatile — it is there to taste, not to fade into the background.
Growing Thai basil at home
Thai basil grows in warm weather and full sun, much like sweet basil. It needs soil that drains well, regular watering, and temperatures above 50 degrees Fahrenheit. In cold climates, it is grown as an annual and dies at the first frost. In warm climates, it can survive year-round or be brought indoors in winter. The plant reaches 12 to 18 inches tall and produces small purple or white flowers if left unharvested.
Pinch off the top leaves regularly to encourage bushier growth and delay flowering. Once the plant flowers, the leaves become less flavorful, so harvesting the growing tips keeps the plant productive. Thai basil grown at home tastes stronger and fresher than store-bought, and a single plant in a pot can supply enough for regular cooking if you harvest consistently.
Thai holy basil and lemon basil: related but different herbs
Thai holy basil (also called tulsi or sacred basil) is used in some Thai dishes but is a separate plant with a different flavor. It has a sharper, more peppery taste with hints of clove and almost no sweetness or licorice notes. The leaves are smaller and rounder than Thai sweet basil, and the plant has a more compact shape. Holy basil is often used in dishes like pad krapow (basil stir-fry) alongside or instead of Thai sweet basil, depending on the region and the cook's preference.
Lemon basil is another Southeast Asian variety with a citrus flavor instead of licorice. It is less common in Thai restaurants but appears in some regional dishes and in Southeast Asian cooking more broadly. All three — Thai sweet basil, holy basil, and lemon basil — are sold at Asian markets, but they are not substitutes for each other. A recipe calling for Thai basil will not work the same way with holy basil or lemon basil, because the flavor profile is too different.
Frequently Asked Questions
Can I use Italian sweet basil instead of Thai basil in a recipe?
Not as a direct substitute. Sweet basil is much milder and lacks the licorice and anise notes that define Thai basil's role in the dish. The final flavor will be noticeably flat. If Thai basil is not available, you can add a small amount of sweet basil and a pinch of fennel seed or anise seed to approximate the flavor, but it will not be the same.
Does Thai basil lose flavor when cooked?
Yes. Thai basil's volatile oils — the source of its licorice and anise flavor — break down with prolonged heat. This is why it is added at the end of cooking or used as a garnish. If you add it at the start of a long simmer, most of the flavor will be gone by the time the dish is done.
Where do I buy Thai basil if my local store does not carry it?
Asian grocery stores almost always stock it, either fresh or frozen. Farmers markets often have it in summer and early fall. Some mainstream supermarkets carry it in the produce section if they have a strong Asian foods department. Online seed companies sell seeds if you want to grow your own.
What is the difference between Thai basil and holy basil?
Thai sweet basil has a licorice and anise flavor with sweetness. Holy basil is sharper and more peppery with almost no sweetness. They look different too — holy basil has smaller, rounder leaves. They are used in different dishes and are not interchangeable.
Can I freeze Thai basil for later use?
Yes, but the texture will soften. Freeze it in ice cube trays with water or oil. It works best in cooked dishes after freezing, not as a fresh garnish. Fresh Thai basil stored in the refrigerator lasts three to five days and tastes better than frozen.