A citron is a large, thick-skinned citrus fruit (Citrus medica) that looks similar to a lumpy lemon but is fundamentally different in structure. Unlike most citrus you’d find at a grocery store, the citron is almost entirely rind and pith, with very little juice or pulp inside. It’s one of the original ancestor species of the entire citrus family, and nearly every citrus fruit you eat today, from lemons to oranges, traces part of its genetic lineage back to the citron.
How a Citron Differs From a Lemon
The most common confusion is between citrons and lemons, which makes sense since lemons are actually a hybrid descended from citrons. But once you see a citron in person, the difference is obvious. Citrons are larger, often 6 to 12 inches long, with a bumpy, textured surface. The rind is extremely thick, sometimes making up the majority of the fruit, and the interior is filled with a white, spongy tissue called albedo rather than the juicy segments you’d expect from citrus.
That thick white pith is the whole point. While you’d never try to juice a citron the way you would a lemon or orange, the pith and rind are where all the culinary and aromatic value lies. The outer rind is intensely fragrant, carrying a floral, sweet scent that’s more complex than lemon zest.
The Ancestor of Modern Citrus
The citron is one of three main ancestral branches on the citrus evolutionary tree, alongside pummelos and mandarins. Every hybrid citrus fruit you know evolved from combinations of these original species. Lemons, for example, are a cross between citron and sour orange. Sweet oranges, grapefruits, and limes all trace back through various crosses of these same ancestors. The diversification into the fruits we recognize today happened roughly 1.5 million to 200,000 years ago, making the citron one of the oldest cultivated fruits in the world.
Major Varieties
Etrog
The Etrog is the variety most people encounter in a religious context. It looks like an oversized, rough-skinned lemon and carries deep significance in Jewish tradition, where it’s used during the harvest festival of Sukkot. Not just any citron qualifies. Rabbinical standards dating back centuries require that the fruit come from ungrafted trees, a rule that once made sourcing them a logistical challenge across Europe. For centuries, specific Mediterranean regions, first Corsica, then the Greek island of Corfu, became prized sources for pure, ungrafted citrons. Observant families historically stored their etrogim in finely crafted boxes lined with flax, keeping them fresh for the full seven days of the holiday, since only a fresh fruit could be used in the blessing.
Buddha’s Hand
Buddha’s Hand (Citrus medica var. sarcodactylis) is the most visually striking citron variety. The fruit splits into long, finger-like projections that fan out from the base, resembling an open hand. These “fingers” can reach 6 to 12 inches in length, and the whole fruit can measure up to 30 centimeters. The interior is entirely solid albedo with no juicy pulp and no seeds. What makes it especially valued in cooking and perfumery is the rind’s aroma, which carries notes of violets and osmanthus flowers, largely from a naturally occurring compound called beta-ionone.
The tree itself is small and shrubby, very sensitive to frost, with distinctive oblong leaves that have serrated edges and a slightly crumpled texture. New growth and flowers are tinged purple. There are actually two main clones: one produces only the deeply fingered fruits, while the other produces a mix of fingered and corrugated fruits, some of which contain seeds hanging loosely inside.
How Citron Is Used in Cooking
Because the citron has so little juice, you won’t be squeezing it over fish or into a cocktail. Instead, the rind and pith are the star ingredients. Candied citron peel is the most traditional preparation and has been a staple of European baking for centuries. You’ll find it in Italian panettone, British mince pies, German stollen, and fruitcakes across many cultures. The thick pith candies beautifully, becoming translucent and chewy when simmered in sugar syrup.
To candy citrus peel at home, you combine peels with an equal amount of granulated sugar by weight and massage the sugar into the skins until they release their oils and become fragrant. After sitting for anywhere from a few hours to a full 24 hours, the peels turn treacly and release most of their aromatic oil. Both the candied peels and the infused oil keep in the fridge for three to four weeks, or in the freezer for up to a year. The chopped peel works in cookies, cakes, and anywhere you want a bright citrus flavor without acidity.
Buddha’s Hand is particularly popular with home cooks and chefs because it’s all zest and no bitterness. You can grate or slice the entire fruit, pith and all, into salads, vinaigrettes, or cocktail garnishes. Some people simply keep one on the kitchen counter as a natural air freshener, since the fragrance is strong enough to scent a room.
Fragrance and Essential Oil
Citron’s aromatic properties extend well beyond the kitchen. Citrus essential oils, including those from citron, are widely used in beverages, cosmetics, and perfumes. The oils are extracted either through cold pressing, where the peels are agitated vigorously with water to release the oil, or through steam distillation. Each method produces a slightly different chemical profile, which is why citron essential oil can smell different depending on how it was made.
The oils are rich in terpenes, the same class of aromatic compounds found in pine, lavender, and cannabis. One of the most abundant is limonene, which gives citrus its characteristic smell and also serves as a building block for other flavor and fragrance molecules with antimicrobial and anti-inflammatory properties. Other compounds in citrus oils contribute floral, fruity, or green notes, making them versatile ingredients in perfumery.
Traditional Medicinal Uses
Citron has a long history in traditional medicine systems across Asia and the Middle East. In Ayurvedic medicine, it has been used for digestive complaints, bacterial infections, and as a general antioxidant. In Persian folk medicine, citron oil has been applied for musculoskeletal pain, gastrointestinal issues, and nervous system complaints. Like other citrus fruits, the peel is particularly rich in flavonoids, phenolic compounds, and vitamin C, all of which have documented antioxidant activity. The peel also contains pectin, a soluble fiber used in food production and associated with digestive health.
Growing Citron
Citron trees are among the most frost-sensitive of all citrus species, which is why they’ve historically been grown in warm Mediterranean and Southeast Asian climates. They do best in daytime temperatures around 65°F, with a drop of five to ten degrees at night. The trees prefer acidic soil, so growers often add peat to the potting mix to keep the pH low. In cooler climates, citron can be grown indoors in containers, though the trees stay relatively small and shrubby. If you’re in a region with any risk of frost, container growing with the option to bring the tree inside during winter is the practical approach.