The complete citrus care guide for Sydney gardens
Citrus trees are among the most popular of all backyard fruit trees in temperate areas such as Sydney. Citrus include lemons, oranges, mandarins, limes, cumquats and grapefruit, and all can be grown either in the garden or in large containers. To get the best crops from your trees, however, they need attention throughout the year. Follow our tips and seasonal guide to keep your citrus growing well all year round.
Grow all types of citrus in full sun with shelter from cold winds. In cold-winter zones, grow citrus trees against a warm, north-facing wall with shelter from cold southerly winds. If full sun isn’t available, select a spot that receives sun for at least six to eight hours from the morning.
Good soil drainage is vital for healthy citrus, and these plants tend to grow just as well whether in a garden bed or a pot, as long as their needs are met. Always choose a well-drained position for your citrus. If soil in your garden bed is slow to drain, plant citrus into a raised garden bed or large container filled with specialty potting mix (such as Supersoil Rose & Citrus Potting & Planting Mix). Always ensure that any pot or container you use has drainage holes in its base. If using a container, you're best off to choose a variety grafted onto dwarf rootstock - this will help ensure a smaller and more manageable plant with full-sized fruit. Citrus can be planted throughout the year, but the best planting times are autumn to spring (avoid planting in very hot or very cold conditions).
Seasonal citrus care
Citrus trees are evergreen, which means they are leafy year-round. Most varieties flower in spring (or from late winter) with fruit ripening from late summer, however some will flower and fruit throughout the year. Learn more about different citrus varieties here.
Summer citrus care
- Keep plants watered regularly to avoid them drying out. Erratic watering and heavy rainfall as the fruit matures can lead to fruit split, particularly in oranges.
- Feed citrus in mid to late summer with a complete citrus food (follow instructions on the fertiliser bag or container). We recommend Gyganic for Fruit and Citrus. For container-grown plants, apply smaller amounts monthly from summer to early autumn.
- As the crop matures and its weight increases, it may need to be thinned out as weak branches may break under the weight.
- Watch for bugs such as bronze orange bug (pictured left) and spined citrus bug, which attack fruit leaving stink marks on the skin and causing dry fruit. These stink bugs often cluster on trunks in the heat of the day. Squash or remove bugs with care. Wear protective glasses as these bugs squirt an irritating spray to defend themselves.
- Scale may also be noticed on citrus trees in summer (but can affect trees throughout the year). This insect protects itself with a hard waxy covering that is usually white, brown or black. Scale can be found under leaves, on twigs and stems or on fruit. Control by squashing individual clusters and applying horticultural spray oil such as Pest Oil.
- Citrus leaf miner, which causes the growth to pucker and which leaves silver trails in the leaves, is a common sight in summer. While this pest doesn’t affect fruit production it looks unsightly. Success Ultra is your best defence.
- Ants may also be seen on citrus trees often attracted by the presence of scale, aphids or mealy bugs. Controlling the pest usually controls the ants. Black sooty mould on foliage is another sign of pest attack. Removing the pest usually stops the source of sooty mould but it can be removed by spraying with a soap spray (such as Nature's Way Herb and Vegie Spray Natrasoap).
- Mites also frequently cause havoc on citrus during humid summers. Look out for speckled, discoloured foliage, misshapen fruit and webbing under leaves as characteristic telltale signs of mite infestation. Treat with eco-oil.
Autumn citrus care
- Watch ripening fruit for signs of pest attack including possums, rats, birds and fruit fly (pictured right). Protect individual fruit clusters with exclusion bags or net trees where damage is severe using bird- and bat-safe white knitted netting stretched tautly over trees. Check netted trees regularly as animals, birds and reptiles can become entangled.
- Citrus leaf miner may still be causing havoc in your garden through autumn. Treat with Success Ultra.
- Protect fruit from fruit fly by using organic splash baits and lures, such as eco-naturalure. Thin-skinned fruit such as mandarin is particularly vulnerable to fruit fly.
Winter citrus care
- Most citrus fruit holds well on the tree and can be harvested as needed, however mandarins need to be picked when ripe as overripe fruit loses flavour and its skin becomes puffy. To gauge ripeness of fruit, look at size and colour and harvest a sample fruit to check for sweetness. As citrus ripens the fruit usually becomes sweeter in taste. Oranges may re-green after ripening – this is a natural protection against sun damage. Leave tart fruit longer to ripen further.
- Move potted citrus into a frost-free location over winter.
- Winter spray using horticultural spray oil such as Pest Oil to control juvenile life cycle bronze orange bugs.
- Apply complete citrus food such as Gyganic again in late winter, watering well when applying fertiliser.
- Yellowing leaves may indicate nutrient deficiency due to cold conditions. Warmer weather should see an improvement in leaf colour. If yellow leaves persist, apply Yates Leaf Greener Iron Chelate or Yates Health Tonic Trace Element Chelates and check watering.
- Curled leaves often indicate cold exposure. If the tree is exposed to cold, look at ways to provide more shelter such as by erecting a screen.
- Flowering may begin in late winter.
Spring citrus care
- Expect fragrant citrus blossoms in spring. Harvest any remaining fruit (although many lemons happily support mature fruit, immature fruit and flowers).
- Keep plants evenly watered during flowering and fruit formation, especially if spring is dry or trees are exposed to hot, dry winds.
- Immature fruit may be discarded naturally from trees if the weather turns cold, the tree dries out or the crop is too large for the tree to maintain.
- If plants weren’t fed in late winter apply a complete citrus food such as Gyganic in early spring.
- Remove weeds from around the tree and apply a light layer of organic mulch, such as sugar cane mulch, taking care not to mound mulch around the trunk.
- After a quiet winter, new growth may be attacked by citrus leaf miner come spring. Success Ultra should be your go-to product here.
- Also watch out for aphids on new growth. Squash aphids or remove them with a jet of water from the hose. Alternatively, spray with an organic control for aphids, such as Nature's Way Herb and Vegie Spray Natrasoap.
- Citrus trees don’t need pruning to encourage fruiting, however if pruning is needed to control the size of trees, do this in spring. Avoid pruning in summer as exposed wood can become sunburnt. Dead wood can be removed at any time.
Pests and diseases
Citrus plants can be prone to pests and diseases, particularly through the warmer months of the year. For comprehensive advice on combating pests, diseases and nutrient deficiencies, check out this article.