Citrus x limonia – Rangpur Lime

Site: Choose a free draining position in full sun. It will handle more exposure and cold than other limes, but avoid open frost hollows while young.

Soil preparation: Enrich the planting area with quality compost and aged manure to support its vigorous growth.

Hole: Dig twice as wide as the root ball and the same depth.

Planting: Set level with the surrounding soil, keeping the graft union clear, backfill, firm in and water deeply to settle the roots.

Home orchard: 3 metres apart so each canopy develops fully and air moves through.

Informal screen: 2 to 2.5 metres apart for a productive evergreen screen, accepting more pruning.

Feature tree: 3.5 metres apart to allow the full canopy and winter fruit display to develop.

Watering: Water deeply twice weekly through the first 12 months, then weekly in dry spells and while fruit is sizing. It handles dry periods better than other limes once settled.

Mulching: Apply a 5 to 7 centimetre layer of organic mulch across the root zone, keeping it 5 centimetres clear of the trunk.

Pruning: Prune after harvest to open the canopy and hold the tree at picking height. Thin heavy crops on young trees so branches are not damaged.

Fertilising: Apply a complete citrus fertiliser in early spring and again in late summer. Vigorous growth means it uses more than a slower citrus.

Pest and disease: Generally robust. Watch new flushes for citrus leaf miner, and check for scale and aphids through spring and autumn.

Citrus x limonia is the most adaptable of the limes, growing in loam, sandy loam and even moderately alkaline ground where drainage is reliable. Slightly acidic to neutral is still preferred.

Sandy soil: Free draining and suitable. Mulch and feed regularly, as nutrients leach.

Clay soil: Improve with gypsum and coarse compost, or plant on a raised mound.

Loam: The preferred soil for fast growth and consistent heavy crops.

pH: Slightly acidic to neutral preferred, though it tolerates mild alkalinity better than most citrus.

Q: What is a Rangpur lime?
A: Citrus x limonia is a natural hybrid between mandarin and citron, grown as Rangpur lime or mandarin lime. The fruit is the size and colour of a small mandarin but the juice is sharply acidic like a lime. It is evergreen, vigorous and one of the hardier citrus in Australian gardens.

Q: What does Rangpur lime taste like?
A: Sharp and acidic, closer to a lime than to any mandarin, with a distinct aromatic edge from the orange rind. It substitutes for lime in cooking, cordials and drinks, and is the traditional citrus in a gimlet. The flesh is not sweet, so it is not eaten fresh in segments like a mandarin.

Q: How big does a Rangpur lime tree grow?
A: Around 3 to 4 metres tall and 2 to 3 metres wide, with a dense canopy that fills out quickly. Growth is fast for a citrus at 40 to 60 centimetres a year. It responds well to pruning, so it can be held near 2 metres for easy picking or grown out as a small feature tree.

Q: Is Rangpur lime frost tolerant?
A: It is the hardiest of the limes and handles light to moderate frost once established, which makes it a workable choice in districts where Tahitian and Key lime fail. Protect it for the first two winters while young. Prolonged hard frost will still damage flowers and soft growth and cut the following crop.

Q: Do I need more than one tree?
A: No, it is self fertile and a single tree crops heavily. Flowering is mainly in spring with sporadic flushes afterwards, and fruit colours through winter. Cropping is usually so generous that thinning matters more than pollination, particularly on young trees carrying more fruit than the branches can hold.

Q: Is it useful as a rootstock or ornamental?
A: It has long been used as a citrus rootstock for its vigour and its tolerance of dry and saline soils, which is also why the tree itself is so tough. In the garden the combination of dark foliage and heavy crops of bright orange fruit over winter earns it a place on looks alone.

Q: How do I care for a Rangpur lime?
A: Water deeply while it establishes and through fruit development, then treat it as moderately drought tolerant. Feed with citrus fertiliser in early spring and late summer. Prune after harvest to keep the canopy open, thin heavy crops on young trees, and monitor for scale, aphids and citrus leaf miner on new flushes.