For me, it depends on the age of the tree, and where they are planted.
Some area's of my yard are basically that white/rocky road fill type of soil that gets bone dry. There are no sprinklers in that area, and the grass dies due to draught. I have about 10 trees less than 3 yrs old planted in that area, and I feel it is necessary to deep water them every week or 10 days, even though some of them are holding fruit.
In areas with more forgiving soil, and trees over 3 yrs old, I do not water.