Starting to put partially buried pots in ground about 3" with holes on sides. The idea is for roots to eventually go into the soil, after initial watering do I set up the drip emitter to water the pot or the ground next to the pot?

What about future fertilization? Is it better to feed the pot or ground around the pot?

Rayvino, good question. In my opinion, the reason to partial bury the pot is to hold down the temperature of the pot and to give some stability to the tree from the wind. Sure some roots will escape from the pot and aid nourishing the tree. After the growing season the pots are dug up and removed for winter storage. Any escaping roots are cut off at that time. I try to use large pots and water /fertilize within the pot. This will encourage root growth within the pot. I think watering outside will encourage more root growth outside of the pot. Digging the tree out at season's end you will be cutting off the roots that the tree has become dependent on. Each new year you may have to increase the pot size or eventually root prune the tree.

I put the drip emitter in the pot for a few weeks until the roots establish themselves outside the pot then turn the emitters off.  Once the roots are out of the pot, they rarely need watering.