How to grow yuzu
Overview
Yuzu (Citrus junos) is a hardy evergreen citrus prized for its fragrant blossoms, glossy foliage, and aromatic fruit. It is a cold-tolerant species that thrives in warm, sunny gardens, making it an excellent choice for both ornamental and productive use in cooler Australian climates.
Varieties
- Yuzu — The standard variety, widely available in Australian nurseries, known for its cold tolerance and aromatic fruit.
Soil Preparation
Yuzu prefers slightly acidic soil (pH 5.5–6.5) with good drainage. Before planting, incorporate well-rotted compost or aged manure, and add a handful of gypsum if soil is heavy. Ensure the site is free from waterlogging, as roots are sensitive to rot.
Growing Guide
Plant yuzu in a sunny, sheltered position with well-drained soil; avoid heavy clay or waterlogged sites. Space trees 3–4 m apart, or grow in a large container (50 cm+). Dig a hole twice the width of the root ball, backfill with compost and native soil, and water deeply. Mulch with organic matter to retain moisture, but keep mulch away from the trunk. Stake young trees for the first 2–3 years to establish a strong central leader.
Sowing
Yuzu is rarely grown from seed; most are grafted onto rootstock. If sowing, plant seeds 1 cm deep in seed-raising mix, keep moist and warm (20–25°C), and expect germination in 2–4 weeks. Direct sow in spring, but transplant to a permanent position after 1 year.
Care
Feed yuzu with a balanced citrus fertiliser in early spring and late summer, following package rates. Prune lightly after harvest to shape the tree and remove dead or crossing branches. Thin fruit if needed for size, and water deeply during dry spells to prevent fruit drop.
Companion Planting
Plant yuzu near other citrus, herbs like rosemary and thyme, and flowering plants such as marigolds to attract beneficial insects. Avoid planting near eucalyptus or walnut trees, which can inhibit growth. Keep a clear zone around the trunk to reduce pest habitat.
Common Pests & Risks
Common pests include citrus gall wasp (prune out galls in winter), scale (treat with horticultural oil in spring), and leaf miner (use neem oil or remove affected leaves). Monitor regularly for aphids and sooty mould, and encourage natural predators like ladybirds.
Harvesting
Harvest yuzu fruit when it turns deep yellow and gives slightly to gentle pressure, typically from late autumn to winter. The fruit is aromatic and tangy, ideal for zesting and juicing. Pick before heavy frosts to avoid damage, and store in a cool, dry place for up to 2 weeks.
In the Kitchen
Yuzu zest and juice are used in dressings, marinades, and desserts; the fruit is too sour for fresh eating. Store whole fruit in the fridge for up to 2 weeks, or freeze juice in ice cube trays. Use sparingly to avoid overpowering other flavours.
Troubleshooting
Yellow leaves: cause is often nitrogen deficiency or poor drainage; fix with citrus fertiliser and improve soil. Brown leaf edges: cause is salt burn or wind; reduce fertiliser and shelter tree. Fruit drop: cause is water stress or overwatering; maintain even moisture. Sooty mould: cause is scale or aphids; treat pests with oil. Leaf curl: cause is cold damage or pests; protect from frost and treat with neem oil.