Clove oil comes from the flower buds, leaves, and stems of the clove tree (Syzygium aromaticum), an evergreen native to the Maluku Islands in eastern Indonesia. The buds are the most commercially valuable part: when dried, they contain up to 18% essential oil, which is extracted through steam distillation. Today, Indonesia remains the world’s largest clove producer by a wide margin, harvesting roughly 145,900 metric tons in 2023.
The Clove Tree
The clove tree belongs to the myrtle family and thrives in warm, tropical climates with at least 1,500 mm of annual rainfall and temperatures between 16 and 27°C (65–80°F). It needs deep, fertile, well-draining loamy soil to limit water stress, especially in regions with a dry season. A dry period actually helps trigger flowering, which is why the best clove-growing regions have a mix of heavy rain and seasonal dryness.
Young trees first flower at around three to four years old, but their growth and yield remain unstable for the first five years. Trees hit their stride as they mature, reaching a stable and productive phase between 30 and 50 years old. That long productive lifespan makes clove trees a generational crop in many farming communities.
Where Cloves Are Grown
Although the clove tree originated in the Maluku Islands (historically known as the Spice Islands), cultivation has spread across the tropics. Indonesia dominates global production, followed by Madagascar at 26,150 metric tons and Tanzania at 9,140 metric tons in 2023. Tanzania’s production centers largely on the island of Zanzibar, which has been a major clove hub for over a century. Smaller producers like Comoros are growing their output as well.
Which Parts of the Tree Produce Oil
Three distinct parts of the clove tree yield essential oil, each with a different chemical profile.
- Bud oil is the most prized. It’s extracted from the unopened flower buds, which are hand-picked just before they open to maximize size and oil content. This oil has the richest, most complex aroma because it contains higher levels of both eugenol (the compound responsible for that signature warm, spicy smell) and a secondary compound called eugenyl acetate that adds depth to the scent. When people say “clove oil” without further detail, they almost always mean bud oil.
- Stem oil comes from the small stalks that connect the buds to the branch. It actually contains more eugenol than bud oil, but less eugenyl acetate, giving it a sharper, less rounded aroma.
- Leaf oil has the lowest eugenol content of the three and very little eugenyl acetate. It’s the least expensive to produce because leaves are abundant and don’t compete with the spice trade. Leaf and stem oils are often produced from leftover plant material after the buds have been sold, particularly in Indonesia where dried buds are in high demand for the kretek (clove cigarette) industry.
How the Oil Is Extracted
The traditional commercial method is steam distillation. Dried clove buds (or leaves or stems) are placed in a still, and steam passes through the plant material, carrying volatile oil compounds with it. When the steam cools and condenses, the oil separates from the water. The resulting oil is colorless to pale yellow with an intense, unmistakable clove flavor.
Yields vary depending on the extraction method and solvent used. Simple water-based maceration (soaking) pulls about 16% of the bud weight as oil, while more intensive laboratory methods using ethanol can extract as much as 44%. In practice, commercial steam distillation falls somewhere in between, with dried buds typically yielding around 15–20% of their weight as essential oil. That’s an exceptionally high yield compared to most essential oil crops, which is one reason clove oil remains relatively affordable.
What’s Inside the Oil
Eugenol is the dominant compound in clove oil, making up 85–95% of the total. This single molecule is responsible for most of clove oil’s recognizable smell, its warming sensation on skin, and its well-known numbing effect on tooth pain. The remainder consists primarily of eugenyl acetate (which contributes a fruitier undertone) and beta-caryophyllene (a compound with a mild, woody aroma found in many spices).
The exact ratio of these compounds shifts depending on which part of the tree the oil came from, when the buds were harvested, and whether the tree was young or mature. Buds picked just before opening from a mature tree consistently produce the highest-quality oil, with the most balanced blend of all three key compounds.
Why the Harvest Timing Matters
Clove buds are still picked by hand in most producing regions. The timing is critical: harvesters climb the trees and pick the flower clusters just before the first buds in a cluster begin to open. At this stage, the buds are plump, pink-red, and packed with the highest concentration of essential oil. If they’re picked too early, the buds are undersized and the yield drops. If they open into full flowers, the oil content decreases and the commercial value of the spice falls sharply. This narrow harvest window, combined with the need for hand-picking, is what keeps clove farming labor-intensive even in the largest producing countries.