How to grow finger lime
Overview
Finger lime is a slow-growing, spiny shrub native to the rainforests of eastern Australia. It is prized for its elongated fruit containing tart, caviar-like juice vesicles, and is grown both as an ornamental and a productive edible. Key to success is providing well-drained soil and protection from heavy frost.
Varieties
- Rainbow — Produces elongated fruit with pink to red skin and pink pearls, popular for its striking colour.
- Jade — A green-skinned variety with pale green pearls, known for its vigorous growth and heavy cropping.
- Pink Ice — Bears pink-skinned fruit with pale pink pearls, a reliable cropper in temperate gardens.
- Red Champagne — Deep red fruit with red pearls, highly ornamental and productive.
Soil Preparation
Finger lime prefers slightly acidic soil (pH 5.5–6.5) with excellent drainage. Before planting, incorporate 2–3 kg of well-rotted compost per square metre and add a handful of blood and bone. Avoid alkaline or heavy clay soils; if needed, raise beds or add gypsum.
Growing Guide
Plant finger lime in a position that receives morning sun and afternoon shade, especially in hotter zones. Space shrubs 2–3 m apart. Prepare a hole twice the width of the pot and backfill with native soil mixed with well-rotted compost. Water deeply at planting and then weekly until established. Mulch with 5–7 cm of organic matter, keeping it clear of the trunk. Avoid planting in heavy clay or waterlogged sites.
Sowing
Finger lime is rarely grown from seed due to slow and variable germination. Most gardeners buy grafted or cutting-grown plants. If attempting seed, sow fresh seed 1 cm deep in seed-raising mix, keep warm and moist, and expect germination in 4–8 weeks.
Care
Feed with a slow-release citrus fertiliser in early spring and late summer. Prune lightly after harvest to remove dead wood and shape the shrub. Thin out congested branches to improve airflow and light penetration.
Companion Planting
Grow finger lime with other native citrus like desert lime or round lime, and with low-growing herbs such as lemon balm or thyme to deter pests. Avoid planting near eucalypts or acacias that may compete for moisture and nutrients.
Common Pests & Risks
Scale insects and citrus leaf miner are common. Treat scale with horticultural oil in early spring. For leaf miner, use a systemic insecticide or remove affected leaves. Gall wasp can cause swellings on stems; prune out and destroy galls.
Harvesting
Harvest finger limes when the fruit changes colour from green to yellow, pink, or red and detaches easily from the branch. Gently twist or snip with secateurs. Fruit can be stored in the fridge for up to 2 weeks or frozen whole for later use.
In the Kitchen
Slice finger limes in half and squeeze out the pearls to use as a garnish on seafood, salads, or desserts. The pearls can be frozen for up to 6 months. They add a tangy burst to cocktails, ceviche, and vinaigrettes.
Troubleshooting
Yellow leaves: often caused by iron deficiency in alkaline soil; apply chelated iron. Brown leaf edges: indicates salt burn or over-fertilising; flush soil with water. Leaf curl: likely citrus leaf miner; remove affected leaves. Poor fruit set: may be due to insufficient sun or lack of pollinators; hand-pollinate with a brush. Dieback: check for gall wasp or root rot; improve drainage.