I would definitely move it outside. You could always provide a little protection from the cold. An unheated building is one way to do it, but you could also make a covering out of breathable material (burlap, the straw mats sometimes used for planting grass, etc).

Thanks, Brandon. Tonight is the first night that they are predicting a moderate freeze. And we have had no frost warnings before this. It has been an unusually warm October until now. I think I'll wait until it warms up a bit (I'm sure we will have a few more warm days) and then move it out so it won't be too much of a shock. Do you think I should keep it in the pot or plant it in the ground? Not enough light in my shed to keep it in there through the winter.

I think you're right about waiting. A few cool nights would be better than a sudden cold night.

The shed would be used after the weather starts turning cool (and the viburnum has dropped it's leaves). No light would be needed.

Great! Thanks for the advice. Hope it's roots are strong and it survives through the winter.

Viburnum are generally cold hardy and it will probably only be a question of whether the roots freeze. If I were you I would move it outside and mulch it well. For a couple of weeks untill the roots are well established you should keep it moinst an cover it at night.

Thanks, Charlie. I think putting it in the ground will be better protection for the roots than keeping it in the little pot. I can pile leaves on it to try to keep it warm. It's so tiny though that I really worry that it is too small to be outside, but then obviously keeping it indoors is not natural for it. We don't have another freeze warning for the next week so right now I have it on my deck. Do you think I should plant it asap?