|A caliche rock at the orchard|
A. You are fine with a depth that will accommodate the root system (18 inches deep) as long as you have good drainage. Go ahead and plant. As long as these are smaller fruit trees (less than 20 foot or so) you will be fine. They could get by with 12 inches (I would rather see it deeper) if they have to as long as you have good drainage. I would not put them in barrels unless you had too.