Q.Water Requirement
Water requirements for citrus in Bosveld Sitrus at Letsitele area, South Africa.

Certified GKH Gardening Expert
It really depends on many factors, such as the temperature while watering and the size of the tree. I would say that you need at least 2 inches (5cm) per week covering the entire area under the canopy. In hot weather (over 30 C), I would increase that to 4 inches (10 cm) per week. That is for a plant in the ground. If it is in a container, water daily in weather under 30 C and twice daily in weather over 30 C.