- Keep the tree in its original nursery container at least for the first Christmas. You don't want to add the shock of transplanting to the stress of its indoor stay.
- Display the tree indoors for no longer than 10 days. Keep it away from heater vents and fireplaces.
- Decorate with small, cool bulbs.
- Water regularly. One easy way: Dump two trays of ice cubes onto the soil surface daily. As the ice melts, the water trickles slowly down through the root zone.
- In cold-winter areas, before you even bring the tree into the house--and before the ground freezes--dig a planting hole in the garden (the hole should be slightly larger than the container). After its indoor stay, ease the tree's transition from the house to outdoors: First place it on a cool, bright porch for a few days; then move it to a protected place outside where the rootball won't freeze; finally, plant the tree, container and all, in the hole you dug. Spread a 5-inch layer of straw mulch over the top of the rootball to protect roots against freezing weather.
- Water the tree regularly year-round. Trees in containers are much more vulnerable to drying out than trees in the ground, so check often by sticking a finger in the soil; if the top 2 inches of soil are dry, it's time to water. Always provide enough water so a little trickles out the drain holes.
- When new growth starts in spring, feed the tree with controlled-release fertilizer (a formula that releases nutrients over a six- to nine-month period is a good choice).
- Each spring, before new growth starts, gently slide the tree partway out of the pot and check the roots. When they begin to circle the inside of the pot, nip them back with pruning shears, rough up the rootball, and move the tree into a larger pot.