The most common cause of citrus leaf curl are:
- Water stress
- Or all of the above
How to treat citrus leaf curl
Pests: Check for evidence on the underside of the leaves. Spray your citrus tree with insecticidal soap or neem oil or a good insecticide from your garden centre. Repeat until the plant begins to recover. Silvery lines or trail on the new leaves means your tree has citrus leafminer. It's a tiny moth that lays its eggs on the leaf. The hatched larvae tunnel into the leaf and cause the tunnels creating ugly distorted leaves, reducing the harvest on the trees. Spray the plant with Pest Oil or Eco Oil every two weeks ensuring to spray both the top and bottom of the leaves.
Drought: You need to give more water to your fruit trees. Drought stress is the most common cause of leaf curl in citrus, but also the easiest to remedy.
Disease: Several fungal diseases might also be the issues, such as bacterial blast and botrytis disease. Apply copper sprays to trees infected with both, but it could mean a reduction in fruit.
Temperature: Drastic seasonal changes can give your citrus trees stress. They thrive during summer, but if there’s too much heat they can become dehydrated. Also, if it’s too cold in the winter the leaves can become brittle and damaged from the frost. So depending on the climate you can try to balance the temperature accordingly by either providing shade or removing it when you see leaves curling.
The same treatments should work for getting rid of citrus leaf curl, whether you have orange trees, mandarin tree lemon trees, lime trees or peach trees.
Prune and trim
Citrus trees enjoy regular pruning to increase airflow, photosynthesis, and growth. Methods like topping and skirting can help prevent bugs from climbing onto the tree. If left unpruned, your tree will be more prone to the spread of diseases from the soil and other contaminated leaves.