WHY DOES THIS HAPPEN?
The two most typical causes of holes in the leaves of your plant are Shot hole disease or insects.
Shot hole disease, (or Coryneum blight), is a fungal disease that can commonly occur on fruit trees, leading to spots on the leaves that eventually develop into a hole. It typically arises in wet conditions, such as after prolonged rainy periods, and can be spread by splashing water. Therefore, if you believe that your plant may be infected with Shot hole disease, it’s a good idea to avoid overhead watering for a while, to help minimise the spread. It may be necessary to use a fungicide.
Some types of insects feed directly on plant leaves, leaving holes and other damage to the plant. Snails can also cause this kind of damage. Make sure to check the underside of the leaves regularly, as this is often where pests will hide. Some insects can be manually removed, but more advanced infestations may require the use of a pesticide.