The tree is around 4 feet tall. I usually just leave it in the pot is comes in and hope to plant it outside in March. I keep it until then in the house so the sudden change of temperature wont kill it. Maybe I should put it ouside sooner, in case the pot is too small? I have another pot which is slightly bigger than the one it comes in. I wonder if it would be worth transferring it to that one. And it is a prettier pot for Christmas too.
I usually water it now and again. I wait until the soil is dry and then give water. This seems to keep my house plants healthy but not the Christmas trees.
I dont know anything about root systems so I cant coment about that.