Citrus junos seed

LATIN NAME: Citrus junos

COMMON NAME: Yuzu, Japanese Yuzu

Yuzu is the citrus fruit that smells like a whole garden in one peel. It grows as a small, spiny, evergreen tree, usually staying under three or four metres, with glossy dark leaves and thorny branches that make it a useful barrier as well as a fruit tree. The flowers are white and heavily fragrant in spring, and by late autumn the fruit ripens to a round, knobbly yellow globe with thick, bumpy skin. The rind carries an intense, sharp, almost floral scent, somewhere between a mandarin and a grapefruit, and it is this peel, more than the sour flesh, that cooks prize.

Yuzu comes from central China, and it has been grown in Japan and Korea for so long that most people now think of it as Japanese. It is one of the hardiest citrus fruits there is, tolerating frost far better than lemons or oranges, which is why it grows where other citrus will not. The tree is slow and tidy, and it lives for a long time, rewarding patient growers for decades.

Positive & Encouraging Seed Germination Guide

Growing yuzu from seed is a slow pleasure, and it works reliably if you are willing to wait. The seeds are plump and pale, and they benefit from a spell of cool, moist conditions before sowing, so wrap them in damp paper towel and keep them in the fridge for about a month. Then sow them in pots of gritty seed compost, about a centimetre deep, and keep them warm and moist. Germination is often uneven, with the first seedlings appearing in three to six weeks and others following later, so keep the pots going rather than giving up. Grow the young trees on indoors or in a sheltered spot for their first couple of years, and protect them from hard frost while they are small. It takes patience, but a yuzu tree you have raised from seed is a tree you will keep for a lifetime, and the first fruit you harvest from it will make every week of waiting worthwhile.

Scientific Research & Plant Biotechnology

Yuzu has drawn real interest in food and plant science. Its peel is rich in essential oils and antioxidant compounds such as flavonoids and vitamin C, and laboratories have examined the fruit for its aromatic profile and for potential health benefits, including studies looking at stress and inflammation. Because yuzu is so hardy for a citrus, it is used in citrus breeding programs as a cold-tolerant parent, and researchers have studied its hybrids with other citrus to breed tougher, more aromatic varieties. In horticulture, yuzu is propagated by grafting to keep fruit quality uniform, while seedlings are used as rootstocks and in breeding. Between the perfume lab and the citrus orchard, yuzu has a steady and practical record in research.

Ecological & Economic Value & Wide Applications

Ecologically, yuzu is a good tree for a garden. Its spring flowers feed bees and other pollinators, and the dense, thorny canopy gives birds shelter and nesting sites. It needs little once established and, being hardy, it can be grown in regions where other citrus fail.

Its economic value is built on its rind and its scent. Yuzu is a staple of Japanese and Korean cooking, where the zest flavours sauces, marinades, dressings and the famous yuzu kosho paste, and the juice is used in drinks, vinegars and desserts. The essential oil from the peel goes into perfumes, cosmetics and bath products, and fresh and preserved yuzu is exported to markets around the world at premium prices. For a grower, a mature yuzu tree is a long-term asset, and for a gardener it is one of the most rewarding cold-hardy citrus you can choose.