Citrus medica Seeds | Citron
LATIN NAME: Citrus medica
COMMON NAME: Citron
Plant Profile
The citron is the oldest of the cultivated citrus and the strangest to look at: a shrub or small tree of three to four metres, with pale green leaves, purple-tinged new growth, and fruit that can weigh two kilograms and consist mostly of thick white rind.
It is native to north-east India and the foothills of the Himalayas, and it was the first citrus to reach the Mediterranean, long before the orange or the lemon. The variety grown for ritual use, the etrog, is selected for a clean, unblemished skin and a single persistent style. The rind makes up seventy per cent of the fruit, and it is the only part with any commercial value.
Science & Biotechnology
Citron is one of the parents of the modern lemon, and genetic work places it at the base of the citrus family tree along with the pomelo and the mandarin. Its peel is unusually rich in the flavonoid hesperidin and in limonene, and the rind is where most of the aroma sits.
The fingered citron, sold as Buddha’s hand, is a sport in which the fruit divides into finger-like segments and never forms juice sacs. It is grown largely as an offering and as a perfume, since there is nothing inside to eat.
Uses & Benefits
Candied citron peel is the classic use, and it appears in fruitcake, panettone and Christmas pudding across Europe. The peel is boiled in several changes of water, then simmered in syrup and dried. The juice is sour and scarce, and the pulp is usually discarded.
In Jewish practice an unblemished etrog is used at Sukkot, which sustains a specialised and expensive cultivation in Israel and Italy. The fruit is also distilled for liqueur, and the leaf is used in some traditional medicines. Pesticide residues on the skin are a real issue for candying, so organic fruit is worth the price. In Italy the candied peel is diced into a dense, dark bread for Christmas, and the same peel is used in the small pastries of Sicily, where the fruit is grown on terraces above the sea.
Growing from Seed
Seed is usually polyembryonic, producing several seedlings of which only one is sexual; the rest are clones of the mother plant, which is convenient for growers. Sow fresh at 25°C, and expect germination in three to six weeks.
Citron is the most cold-sensitive common citrus and is damaged below about minus two. It needs heat, sun and excellent drainage, and it fruits best in a large container in cool climates, moved under cover for winter. Cuttings of semi-ripe wood root readily and avoid the variability of seedlings. Fruit needs a long, hot season to swell, and a cool summer gives small, thick-skinned fruit.
Our Take
A citrus grown for its peel and its symbolism rather than its juice, and the one citrus worth candying at home if you can find organic fruit.
Related Reading
Gardeners who grow Citron often pair it with these related subjects: