Citrus aurantium – Seville Orange

Citrus aurantium, the Seville or bitter orange, is an evergreen tree with a dense rounded canopy, thorny branches and dark aromatic leaves. The fruit is thick skinned, sour and intensely fragrant, which is exactly why it makes the best marmalade. Spring blossom is the most powerfully scented of any citrus. It is hardier than a sweet orange and tolerates light to moderate frost once established, along with a wider range of soils. Full sun and reliable drainage still matter. Mature size is 4 to 6 metres tall and 3 to 4 metres wide, at 30 to 60 centimetres a year. Use it as a fragrant feature near a path or a seating area, in a productive orchard row, or clipped as a formal standard in a courtyard. It has long served as citrus rootstock, so the tree itself is tough. Worth planting for the blossom alone, with the marmalade fruit a bonus. Frequently Asked Questions About Seville Orange What is a Seville orange?Citrus aurantium is the bitter or sour orange, a distinct species from the sweet orange. The fruit is thick skinned, high in pectin and far too sour to eat fresh, but it is the traditional and best fruit for marmalade. The species has also long been used as citrus rootstock. What is Seville orange fruit used for?Marmalade above all, since the high pectin and acid set a preserve without additives. The rind goes into candied peel, bitters, liqueurs and cooking, the juice into marinades and sauces, and the blossom into orange flower water. Very little of the fruit needs to go to waste. How big does a Seville orange tree grow?It reaches 4 to 6 metres tall and 3 to 4 metres wide unpruned, which makes it larger than most sweet oranges. Growth is around 30 to 60 centimetres a year. It responds well to shaping and can be held considerably lower, or trained as a clipped standard in a courtyard. Is the Seville orange thorny?Yes. The branches carry stiff thorns, more so on young vigorous wood, so wear gloves when pruning or picking. Those thorns are one reason the tree makes a useful barrier or boundary planting, but keep it away from narrow paths and areas where children play. How fragrant is the blossom?Strongly. Seville orange blossom is the most heavily scented of the citrus and carries a long way on a warm spring evening, which is why it is distilled for neroli oil and orange flower water. Plant it where you walk past regularly or sit outside during spring. Is Citrus aurantium used as a rootstock?It has been used as citrus rootstock for centuries, valued for vigour, tolerance of heavier soils and resistance to some root diseases. Susceptibility to citrus tristeza virus has reduced commercial use, but the same underlying toughness makes the tree itself dependable and long lived in a garden. How do I prune and care for a Seville orange?Prune after harvest in late winter, thinning the centre for light and cutting back any water shoots. Wear gloves for the thorns. Water deeply while establishing, mulch clear of the trunk, and feed with citrus fertiliser in early spring and late summer. Remove suckers below the graft.