Thanks for buying a live tree! We're in Massachusetts, and had success under the direction of a horticulturist.
The tree must be inside for the least possible amount of time, no more than a week or two, so don't buy it too many days before Christmas, and plant it as soon as you can after the holiday. Too much time in a warm dry room will cause difficulty adjusting to its natural conditions. It may even sprout new growth that will die once you put it out, compromising the entire tree.
Our tree was dug up the day before we got it; stayed in our 3-season room with daytime temperatures in the 50s F, nights in the 30s F; and transplanted out on the 11th day.
You only need sufficient thawed ground and sun in the place you're going to put it, even if other areas are frozen. Even if the ground freezes after you've prepared the hole, you can still plant the tree, using the dirt you dug up. Many people dig the hole earlier in the season.
Caring for and planting live Christmas trees:
Try to plant the tree immediately after the holiday hoopla has ended. The tree should not be stored above ground during the winter if it can be avoided. It’s not a good idea to store it in your garage either, as it is likely to dry out in there. The best place for live Christmas trees is to be is planted in the ground, even if the ground was frozen as soon as the hole was dug. Just set the tree in the hole and backfill the hole with the loose soil you saved in your wheelbarrow.
From Replanting a Christmas Tree:
When you decide to replant a Christmas tree outside after the holidays, you also need to accept that you will not be able to enjoy the tree indoors as long as you would a cut tree. This is because indoor conditions can put a live Christmas tree at risk. Expect that your Christmas tree will only be able to be in the house for 1 to 1½ weeks. Any longer than this, you reduce the chance that your Christmas tree will be able to adapt to conditions outside again.
All trees are susceptible to Transplant Shock. The tree has already been transplanted when you get it. Further transplants increase the stress, so the entire process must be done carefully.
Ours was a four foot tall blue spruce, and came with the roots in a burlap bag. These instructions from our horticulturist worked perfectly.
- Keep the rootball intact in its original burlap (If yours isn't in burlap, the same instructions are fine. Just gather the roots together.)
- Put it in a tub with a diameter just a few larger than the rootball
- Water it every few days from the top, keeping the rootball moist but not soggy or sitting in a lot of stagnant water
- Keep it in a cool room if possible.
- Don't use hot Christmas lights, and only leave them on for short periods of time
- Before purchase, dig a hole at least 36 inches wide and 24 inches deep
- Plant the tree outside within 10 to 12 days
- Set it into the hole with the rootball level with the ground
- Backfill the hole with its own dirt and some light mulch or shredded leaves
- Don't water the hole, the dirt, the rootball, or the tree during planting
- Don't water the tree at all until about 3 months from Christmas, at the end of March
Here are some pictures. The first two are in the house. The second two are the prepared hole.