When I planted my fruit trees I read - RHS book- to take the blossom off the first year so that they concentrate on root growth and structure. It was sad pulling off the open blossoms. Last year, their 2nd year, I had blossom and a small crop of apples, no pears though, and they seem to be really well rooted and stong.
Because I am growing some as cordons and a couple as pyramid shape I do a late summer prune. I will cut off top when weather warms up in early spring from plum