Skip to content

VOLUME DISCOUNTS APPLY AUTOMATICALLY AT CHECKOUT.

All stock is grown, maintained and graded in strict accordance with AS 4373-2007, Australian Standard for Nursery Stock.

How to Deal with Common Tree Diseases and Pests

How to Deal with Common Tree Diseases and Pests

The practical guide to common tree pests and diseases. How to spot them, how to treat them and how to pick disease-resistant trees that avoid trouble.

Pest ControlPlant HealthTree CareTree Disease

Tree health is almost entirely about setup. Pick the right tree, plant it in the right spot, give it the right care and most problems never start. When the occasional issue shows up, early action sorts it out fast.

Pick resilient trees

Modern cultivars are often bred specifically for resilience. Syzygium Resilience handles the psyllid that other Lilly Pillies notice. Better Green Leyland is bred for clean foliage. Magnolia Teddy Bear and Ficus Hillii have very few serious issues. Smart selection sets up easy growing.

Common signs and what to do

Sooty mould. Black film on leaves from sap-sucking insects (aphids, scale, mealybug). Treat the insect and the mould washes off. White oil spray handles light infestations.

Powdery mildew. White dust on leaves in humid weather. Improve airflow, water at the base not overhead, and treat with a sulphur-based spray if needed.

Wet feet. Wilting leaves on a tree in damp soil usually points to drainage. Open up the drainage, mound up or move the tree if caught early.

Scale insects. Hard or soft bumps on stems and leaves. Light infestations rub off, heavier ones respond to white oil applied to all surfaces.

Leaf chewers. Caterpillars, beetles, possums. Check at night if you can't find the culprit by day. Physical barriers or targeted sprays for specific situations.

Prevention is the easy path

Healthy trees shrug off most pressure. Adequate drainage, deep mulching, appropriate watering and correct pruning take care of the basics. Settled trees are resilient trees.

When to call a pro

Heavy structural pruning, large pest populations or unknown issues all warrant an arborist. A second opinion is cheap insurance on big trees.

Frequently asked questions

Are all natives trouble-free?
Natives have their own insects and weather quirks, but Australian-bred cultivars are often the most resilient picks in local conditions.

Can I use systemic insecticides?
For serious situations yes, but always read the label and skip flowering trees during pollinator activity.

How do I know if a tree needs more attention?
Slow new growth in spring, soft or peeling bark and root collar issues all flag a tree that wants a bit more support. An arborist can confirm and set you on the right path.

Compare at a glance

CultivarHeightWidthFormFoliageBest if you…
Syzygium australe 'Resilience'
Lilly Pilly Resilience
4-6m (can be pruned to desired height)2-3mUpright, denseGlossy green with coppery new growthFormal and informal hedges, screens, native gardens.
Ficus microcarpa var. hillii
Ficus Hillii
5-10m (can be pruned to desired height)2-4mUpright, dense when hedgedGlossy dark green, denseHedges, screens, low-maintenance privacy.
Magnolia grandiflora 'Teddy Bear'
Magnolia Teddy Bear
4-6m2-3mUpright columnarGlossy dark green with cinnamon undersideFormal hedging, narrow screens, courtyards.
Cupressus leylandii 'Better Green'
Better Green Leyland Cypress
5-10m (can be pruned to desired height)2-3mUpright, columnar to pyramidalBright green dense fan-like foliageTall fast hedges, formal screens.

1. Syzygium australe 'Resilience' (Lilly Pilly Resilience)

Resilience is the psyllid-resistant Lilly Pilly. Bred specifically to beat the pimple psyllid that wrecks older Lilly Pilly varieties.

Type
Evergreen Australian native hedging tree
Height
4-6m (can be pruned to desired height)
Width
2-3m
Growth rate
Fast
Foliage
Glossy green with coppery new growth
Form
Upright, dense
Conditions
Full sun to part shade, moist well drained soil
Maintenance
Low
Best for
Formal and informal hedges, screens, native gardens.

Why choose it

The disease-resistant pick. If you've had trouble with psyllid damage on older Lilly Pillies, Resilience solves the problem.

Perfect pair

Use Resilience as a hedge with a Magnolia Coolwyn Gloss feature in front. Both disease resistant, both polished.

Tips for planting

Plant 70-80cm apart for a fast dense screen. Mulch and water through establishment.

The psyllid-proof Lilly Pilly.

Shop Syzygium australe 'Resilience'

2. Ficus microcarpa var. hillii (Ficus Hillii)

Ficus Hillii is one of the most disease-resistant evergreens on the market. Few serious pest issues and tough disease tolerance.

Type
Evergreen hedging tree
Height
5-10m (can be pruned to desired height)
Width
2-4m
Growth rate
Fast
Foliage
Glossy dark green, dense
Form
Upright, dense when hedged
Conditions
Full sun to part shade, well drained soil
Maintenance
Low
Best for
Hedges, screens, low-maintenance privacy.

Why choose it

Few diseases trouble Ficus Hillii in Australian conditions. Watch for thrips in heat but rarely a serious issue.

Perfect pair

Plant Ficus Hillii as a hedge with a Crepe Myrtle Natchez feature out front.

Tips for planting

Keep airflow good through regular pruning. Avoid overhead watering at night.

The bombproof evergreen hedge.

Shop Ficus microcarpa var. hillii

3. Magnolia grandiflora 'Teddy Bear' (Magnolia Teddy Bear)

Teddy Bear is one of the cleanest evergreen Magnolias. Glossy foliage rarely shows disease, and pest issues are minimal.

Type
Evergreen feature/screening tree
Height
4-6m
Width
2-3m
Growth rate
Moderate
Foliage
Glossy dark green with cinnamon underside
Flowers
Large cream summer flowers
Form
Upright columnar
Conditions
Full sun to part shade, rich well drained soil
Maintenance
Low
Best for
Formal hedging, narrow screens, courtyards.

Why choose it

The waxy leaf cuticle resists most fungal issues. Few pest problems in Australian gardens.

Perfect pair

Pair Teddy Bear with an Acer palmatum out front. Both clean, low-disease trees.

Tips for planting

Keep mulch off the trunk to prevent collar rot. Light pruning only.

Refined and disease resistant.

Shop Magnolia grandiflora 'Teddy Bear'

4. Cupressus leylandii 'Better Green' (Better Green Leyland Cypress)

Better Green is the improved Leyland Cypress, selected for stronger disease resistance over the original Leighton Green.

Type
Evergreen conifer hedge
Height
5-10m (can be pruned to desired height)
Width
2-3m
Growth rate
Fast
Foliage
Bright green dense fan-like foliage
Form
Upright, columnar to pyramidal
Conditions
Full sun to part shade, well drained soil
Maintenance
Low to moderate, prune yearly to maintain density
Best for
Tall fast hedges, formal screens.

Why choose it

Improved resistance to needle blight and root issues compared with the original. Quick to screen.

Perfect pair

Use Better Green as a tall screen with a Magnolia Coolwyn Gloss feature in front. Both disease resistant.

Tips for planting

Don't plant in waterlogged soil. Maintain airflow through regular pruning.

The disease resistant fast conifer hedge.

Shop Cupressus leylandii 'Better Green'

Frequently asked questions

Are all natives trouble-free?
Natives have their own insects but Australian-bred cultivars are often the most resilient picks.
Can I use systemic insecticides?
For serious situations yes, but always read the label.
How do I know if a tree needs more attention?
Slow new growth in spring, soft bark and root collar issues flag a tree that wants more support. An arborist can confirm and set you on the right path.