If it's in a pot, and you have it already, then you could as long as you have acid soil and prepare the planting hole well....also, water it well for its first year, with rain water if possible.

If you're thinking of buying one, then I'd wait until spring to get it and plant it.

Agree with the above, but also would say I wouldn't dream of planting anything right now without a pipe in for watering it, but then I live in the South and the soil's like the Sahara, and it would be utterly impossible to keep the roots moist in the ground with the use of a water pipe. Otherwise, wait till mid September to plant when the weather's cooler and possibly more damp.