Cumquat 'Nagami' fruit at LCG (photo credit: Graham Bond)
Cumquat 'Nagami'
Fortunella margarita (previously classified as Citrus japonica)
Rutaceae family
This is no longer classified as a true citrus, but considered a close relative. It is a slow-growing, compact tree that will eventually grow to 3m tall if you let it.
Flowers generally form in late spring or early summer, followed by fruit in late winter that hold well on the tree.
The small oval fruit is eaten skin and all, straight from the tree – the peel is quite sweet, but the flesh is slightly sour. The fruit makes an excellent jam, and when soaked in brandy, make a magical treat.
Native to China.
Tree Maintenance (Citrus)
Pruning
Fortunella margarita (previously classified as Citrus japonica)
Rutaceae family
This is no longer classified as a true citrus, but considered a close relative. It is a slow-growing, compact tree that will eventually grow to 3m tall if you let it.
Flowers generally form in late spring or early summer, followed by fruit in late winter that hold well on the tree.
The small oval fruit is eaten skin and all, straight from the tree – the peel is quite sweet, but the flesh is slightly sour. The fruit makes an excellent jam, and when soaked in brandy, make a magical treat.
Native to China.
Tree Maintenance (Citrus)
Pruning
- When mature, prune half the tree after harvest to keep it healthy and shaped.
- Remove dead, inward facing or crossing branches. Remove any suckers from the rootstock below the graft.
- During establishment, water slow and deep each fortnight, more often if very dry or hot. As it matures, the tree will become more drought tolerant.
- Watering may be needed when young fruit is forming.
- Spring: liquid seaweed, compost around drip line.
- Summer: Compost around drip line, poultry manure, worm wee (10:1).
- Autumn: liquid seaweed, compost around drip line, sulphate of potash, poultry manure.
- Avoid applying fertiliser while trees are preparing to flower, flowering and up until fruit are larger than marbles.
- Keep soil well mulched, leaving a gap around the trunk to avoid collar rot.
- Spray with horticultural oil if sap-sucking insects or scale occur (avoid spraying on days where temperatures may reach above 30°C, or foliage can become burnt). Black sooty mould on the leaves is a symptom of these pests; ants are also an indicator that there is a problem, as ants will farm and protect the insects in order to consume their sweet secretions.
Cumquat 'Nagami' at LCG January 2025 (photo credit: Jacqui Lachmann)
Cumquat 'Nagami' at LCG September 2023 (photo credit: Graham Bond)
