purple leaf plum tree

Hello! I planted four purple leaf plum trees, fairly young (about 10ft tall) in my sideyard last June. They didn't do great, because I guess they were planted the wrong time of the year? They looked very frail all the time and now in the winter they have lost all their leaves, which I assume is...

I need knowledgeable advice as trees are not at all my expertise. I live in a typical residential community in a mid-sized Iowa town. A couple of years ago I had to remove the only 2 trees from my south-facing front lawn. Two autumns ago I planted a fledgling purple leaf flowering plum to...