When growing Oranges you will need to plant it in a position that recieves at least six hours sun a day in free draing soil, with mulch around the roots and a deep watering once a week .If planting in a pot a premium grade potting mix is preferred then regular watering and fertiliser is required. Citrus are quite heavy feeders so in a pot an organic liquid food once a month would be ideal and in the ground a complete fertiliser at the start of Spring and again at the start of Summer and Autumn. Prune after fruiting to keep its shape.
Here in SE Qld Citrus can be prone to an insect called “Citrus leaf miner”. These tiny little moths lay eggs on the soft new leaves and upon hatching the tiny grub burrows into the leaf leaving a squiggly silver trail and causing the leaves to look distorted and curled. The presence of this insect does not affect the flower or fruit , but makes the plant look very unattractive and eventually limits the plants ability to photosynthesis properly. It will cause the tree to be stunted and unhealthy.
If you notice any distorted or curled leaves on the new growth of your citrus, cut them off them as they may contain the eggs or larvae. Then to help stop re-infestation regularly spray the new growth with White Oil, Pest Oil or Eco Oil . This helps prevent the insect from laying eggs on the leaves. Do this every 7-10 days