First, read this and make sure you have all the bases covered. It's called 'sick tree' treatment but it will also help keep healthy trees from getting sick and to grow at their best: howard-s-sick-tree-treatment-t1074.html
As for water, I think it's a mistake to base watering strictly on a time schedule. Watering should be done based on when the soil actually needs it. In other words, if you stick your finger an inch down into the soil in the tree's root zone and the soil is still moist, you don't need to be watering yet. But when you do water, really drench the soil so that it goes down deep. If you only water a little bit every few days, the water won't get down deep into the soil and consequently the tree roots will only concentrate up toward the surface. Also, if the soil is kept too wet you might end up inadvertently breeding some bad fungi, or even killing trees that don't like 'wet feet.'
Make sure you put down a thin layer of compost mixed with cornmeal, greensand, etc over the root zone and then a nice thick layer of mulch on top of that (careful to keep it off the trunk) and this will help keep moisture in the soil while also moderating soil temperature and nourishing beneficial fungi and bacteria that will help fight off disease.
Also, get yourself some Garrett Juice and Thrive (by Alphabiosystems). Those make a potent combination for feeding your trees. You might also pick up some SuperThrive, which is a combination of vitamins and hormones that will help your trees develop.
See attached picture for what we do for watering new trees. 5 gallon bucket with 1/4 inch hose inserted at lowest level allows you to put fish, garrett juice, etc in with the water and it comes out over a period of time (maybe an hour or so) and really drenches the root zone. I don't have pictures, but we make filters to put on each end of the hose to keep stuff from clogging it. Works quite well.