Tree Troubleshooting
Tree Troubleshooting is your practical guide from Easy Big Trees to identifying common tree diseases and health problems. Learn what symptoms to look for, what causes them and the steps we recommend to restore strength, colour and long‑term vitality. This page brings together clear explanations, real examples and proven solutions to help you keep your trees healthy and thriving across New Zealand.
| Species | Issue | Cause | Solution |
|---|---|---|---|
| Bugs on underside of leaves, ‘sticky’ plants. | Spray the plants in late spring/early summer with an insecticide. Soapy water can also be effective. | ||
| Floppy, dull brown new growth at tips. Slightly older leaves may be a dull green to brown colour also. | Heavy frosts, early autumn frost or late spring frost. | Once frost damage is obvious nothing can be done to reverse it. To avoid frost damage, trees should be planted in an area more sheltered from the hardest frosts or given protection (such as frost cloth) while getting established. | |
| Natives – Fertiliser | General nutrient questions rather than symptoms. | Natives naturally grow in low‑nutrient soils and are not heavy feeders. | Use natural fertilisers such as blood and bone, compost or sheep pellets. Apply lightly to avoid burning roots. |
| Confusion between species. | Similar appearance but different growth habits. | Kanuka grows taller with a nicer tree form. Kanuka flowers Oct–Feb; Manuka flowers all year. Kanuka flowers are about half the size of Manuka. Manuka tolerates poorly drained soils; Kanuka does not. | |
| Stress symptoms, leaf issues, blossom problems. | Wet–dry extremes. Temperature swings (30° down to 5–10°). Susceptibility to fruit‑tree diseases. Weather fluctuations during blossom | Ensure good drainage. Avoid planting too deep (top of rootball level with ground). Treat and spray as you would fruit trees. | |
| All Species – Shot Hole Disease | Brown spots that fall out, leaving ‘bullet holes’ in leaves. | Water sitting on foliage for long periods (overhead irrigation or wet Spring). | Avoid overhead watering; use drippers. Spray before leaf‑out to prevent infection. Disease does not kill the tree or affect growth. |
| Pest or disease stress similar to other Prunus species. | Being part of the fruiting Prunus family, so susceptible to similar issues. | Winter copper & oil spray. Occasional systemic insecticide. Check for caterpillars. Soapy water can deter pests. Avoid overly damp soil. Apply general fertiliser (foliar + granular). | |
| Yellowing leaves and possible leaf drop in Summer. | Lack of water; Ulmus require high moisture. | Reinstate consistent watering. Trees usually recover the following season. | |
| Browning or thinning foliage. | Running too dry while establishing (common in Thuja and other conifers). | Improve watering consistency, especially during establishment. | |
| Fruit Tree Spraying Programme | General disease and pest management needs. | Overwintering pests, fungal diseases, poor hygiene, incorrect timing. | Step 1: Prune out dead/diseased wood and remove mummified fruit.Step 2: Apply Lime Sulphur before new growth appears.Step 3: Three weeks later, apply copper spray before buds open.Step 4: One week later, apply spraying oil (e.g. Conqueror Oil).Step 5: Final pruning on a clear day; sterilise tools if disease is present. |
Information provided is intended as a reference only. Growing conditions, climate and site factors can vary widely and may affect outcomes.
We strongly recommend seeking advice from your landscape installer, landscape architect or landscape professional before planting or applying any treatments.
No responsibility can be taken for the use of this information.
