Posted: 23/09/2014 at 08:03
I think you can grow trees in pots, and as Tootles says you have to care for them in a number of ways. Watering will wash out the compost gradually and the tree will become root bound just like any pot plant. Therefore you will need to repot as it grows larger and larger. You will in all probability find it eventually starts to deteriorate and then the choice is yours as to whether to keep it or start again.
One problem is they do blow over in wind. Go for a square pot and use john Innes compost, not MPC. This will help.
If you want to grow eucalyptus, which in the wild is a forest tree, you have the option of cutting it back regularly and then you will get much more attractive foliage than the tree would have. But it is a bush when treated this way, and I wouldn't grow one as a tree in a pot.
In gardening I find that part of the fun is trying new things and not necessarily following accepted conventions. The tree has 2 chances. Go for it and good luck to you both.