Citrus australasica
Finger Lime, botanically known as Citrus australasica, is one of Australia’s most exciting native food plants. Native to the subtropical rainforests of northern New South Wales and southern Queensland, it is increasingly grown by home gardeners, commercial orchards and chefs seeking unique native ingredients.
Often referred to as “Citrus Caviar”, Finger Lime produces elongated fruits filled with tiny juice-filled vesicles that burst in the mouth. These bead-like pearls provide an intense citrus flavour and have become highly prized in restaurants around the world.
The fruit varies enormously in colour depending on the variety, with skin colours ranging from green and yellow through to pink, red, purple and almost black. The pulp itself may be green, pale yellow, pink, ruby red or deep crimson.
Once considered a niche bush tucker species, Finger Lime has become one of Australia’s most commercially successful native food crops.
Plant Information
- Botanical Name: Citrus australasica
- Former Botanical Name: Microcitrus australasica
- Common Names: Finger Lime, Native Finger Lime, Citrus Caviar
- Plant Type: Evergreen native citrus
- Height: 2–6 metres
- Width: 2–4 metres
- Position: Full sun to part shade
- Soil: Well-drained, humus-rich soil
- Fruiting Season: Summer to autumn
- Frost Tolerance: Light to moderate frost
- Pollination: Usually self-fertile, although cross-pollination can improve yields
How To Grow Finger Limes – Basic Care
Growing Conditions
Finger Lime naturally grows as an understory rainforest tree and performs best when given similar conditions.
Position
Choose a position with at least six hours of sunlight each day. In hotter regions some afternoon protection can be beneficial.
Soil
A fertile, well-drained soil enriched with organic matter is ideal. Avoid poorly drained positions.
Water
Regular watering is important during establishment and while fruit is developing. Extended dry periods may lead to fruit drop.
Mulch
Apply mulch around the root zone to maintain moisture and improve soil structure.
Fertiliser
Use a low-phosphorus native plant fertiliser in late winter before flowering or immediately after fruiting.
Yellowing foliage often indicates a lack of nitrogen.
Quick Tips
- A position with at least 6 hours of sun is required for good fruiting.
- Plant in a humus rich well drained soil.
- Mulch around the plant to retain some moisture.
- Fertilise each year.
Growing Finger Limes in Pots
Finger Limes are excellent container plants.
- Use a premium-quality citrus potting mix.
- Ensure excellent drainage.
- Choose a large container.
- Water consistently during fruit development.
- Feed regularly with a suitable citrus fertiliser.
Container-grown plants are ideal for courtyards and smaller gardens.
Rootstocks and Grafting
Most Finger Lime trees sold by nurseries are grafted onto commercial citrus rootstocks.
One of the most widely used rootstocks is Poncirus trifoliata, valued for its vigour, disease resistance and adaptability to a range of soil conditions.
Grafted plants generally begin fruiting within three years, while seed-grown plants may require ten years or more before producing fruit.
Harvesting and Bush Tucker Uses
Finger Limes have been used by Indigenous Australians for thousands of years and are now regarded as one of Australia’s signature bush tucker ingredients.
The fruit is harvested when fully coloured and slightly soft to the touch. When cut open, the finger-shaped fruit releases hundreds of tiny juice vesicles that resemble caviar.
When and How to fertilise Finger Limes.
A native plant fertiliser (low phosphate) is best applied in late in winter bbefore flowering or when the trees have finished flowering and fruiting, this will assist with growth especially in the early years. Yellowing leaves are a sign of lack of nitrogen.
From seed, trees can take 10 – 15 years to reach fruiting size. The gifted tree that are commonly sold will fruit from 3 years on and reach a\the stage where they bear good amounts of fruit at 5 – 7 years.
If your finger lime is not fruiting or the fruit is dropping, it is most likely due to a lack of water and, or a lack of sun.
What Does Finger Lime Taste Like?
The flavour varies between cultivars but is generally described as a refreshing blend of lime, lemon and grapefruit with subtle herbal notes.
The individual vesicles burst when eaten, releasing an intense citrus flavour.
Finger Lime as an Australian Native Food
Finger Lime has become a favourite ingredient among chefs because of its distinctive texture and flavour.
Unlike conventional citrus fruits, the individual juice pearls can be used as a garnish without adding excess liquid to a dish.
Common culinary uses include:
- Seafood and oysters.
- Prawns and shellfish.
- Sushi and sashimi.
- Salads.
- Desserts.
- Cocktails and mocktails.
- Sparkling water and gin.
- Sorbets and ice creams.
- Sauces and dressings.
The colourful pulp adds visual appeal while providing a fresh citrus burst.
Native Food Industry
Finger Lime is now cultivated commercially throughout Australia and exported internationally. The fruit is widely used in restaurants, specialty food products and premium beverages.
Finger Lime Varieties
Increasingly popular both for home gardeners as well as commercial fruit growers a number of hybrids are now appearing on the market with different characteristics to the species.
All have different characteristics including ripening times, with perhaps WG2 being the sweetest. some varieties, such as Alstonville have very few seeds, which can be desirable. Finger limes include cultivars such as:
- Alstonville
One of the most popular varieties with excellent fruit quality and relatively few seeds. - Pink Ice
Highly regarded for its attractive pink pulp. - Tambo
Reliable and productive with good flavour. - WG2
Often considered among the sweeter Finger Lime selections. - NY7
A productive cultivar with good fruit size. - R13
Popular for commercial production and consistent fruiting.
Different cultivars vary in fruit colour, flavour, seed content and ripening period.
Did You Know?
The Red Centre lime or Blood Lime, is a different fruit to the Finger Lime, this one is a hyrax (cross) between the Finger Lime and a Mandarine and is grafted.
The flesh of the Red lime, the’ teardrop shaped caviar’, develops different colours as the fruit continues to ripen. Early harvest fruit will have a lemon /lime coloured flesh. As fruit continues to ripen the colours change to more pink/orange hues, and finally when fully ripe flesh can become quite dark pink.
Where To Buy
Specialist Native Food Nursery with thirty species available in both forestry tubes and 14 cm pots, from ground cover to canopy. Twenty years experience supplying landscape scale projects to backyard gardens.
www.peppermintridgefarm.au .
146 Dignams Crk Rd via Narooma NSW 2546
Tubestock - [50mm forestry tubes and 70mm supertubes] specializing in Bush Tucker Plants , Natives indigenous to the NSW South Coast , Permaculture Plants - Fruits, Nuts & Berries .
www.southcoastflora.com.au