Originally published Dec. 6, 2017
By Ciscoe Morris, former In the Garden writer
PLANTING A LIVING Christmas tree in the garden is a great way to commemorate a special holiday. If you want your tree to be long-lived, however, you’ve got to take steps to keep it from breaking dormancy in your home.
The first step is to gradually acclimate the tree to increased warmth by keeping it in an unheated garage for a couple of days before bringing it into the house. When you move it inside, place the tree in a watertight container, and surround the rootball with sawdust or mulch to hold moisture and to help keep the tree upright. Water enough to keep the rootball moist at all times, but don’t let it sit in water.
Locate your living Christmas tree in a bright spot, but away from heat sources such as a heater vent or TV, and decorate with nonheat-producing LED lights.
Set the thermostat below 70 degrees, and keep the tree inside for no longer than seven to 10 days.
When you take the tree out of the house, if temperatures are mild, plant it in its permanent location as soon as possible. If the ground is frozen, keep the tree in an unheated garage, and wait to plant it until temperatures moderate. If, while in the house, your tree breaks dormancy and begins to grow, you’ve got yourself a big houseplant. It can’t be safely planted outside until conditions warm up in the spring.
Choose your tree carefully. Trees sold as living Christmas trees are specially grown for that purpose. Unlike trees routinely sold as landscape trees, living Christmas trees are sheared to promote thick growth and to give them the traditional Christmas-tree shape. The other difference is that trees sold as living Christmas trees are field-grown and dug only days before they are brought to the nursery or tree lots, while landscape trees are generally container-grown.
During the years I directed grounds care at Seattle University, we planted a number of trees that had been displayed as living Christmas trees. I found that spruces and pines were the easiest to transplant and usually could make the transition from Christmas tree to landscape specimen with few problems.
Some of the true firs, on the other hand, were less likely to survive when planted into the garden after the holidays. If you want to use a noble, grand or white fir for your living Christmas tree, choose one grown for use as a landscape tree. It might look a bit “Charlie Brown-ish” compared to the sheared ones, but the odds that your tree will survive to become a beautiful, long-lived addition to your landscape will be greatly enhanced.
Also, don’t forget that some of those cute little living Christmas trees can turn into 60-to-100-foot behemoths. Before you make a choice, ask a nursery employee how big the tree is capable of growing. If you plant a tree that will turn into a giant too near the house, or if it grows too big for your garden, your living Christmas tree of 2017 could end up expensive firewood in 2047.
You still can have a living Christmas tree, even if you don’t have room to plant one in your garden. Although they aren’t hardy, Norfolk Island pines (Araucaria heterophylla) are highly attractive, easy-to-grow conifers that make beautiful, long-lasting houseplants. Nontoxic to pets and children, these small trees feature symmetrical, horizontally tiered branches and dark-green leaves that look fantastic decorated with lightweight ornaments and a string of LED mini-lights.
All they require to remain beautiful for years is a well-ventilated location in bright indirect light, and occasional misting. Water regularly from spring to autumn, but sparingly in winter, and repot every three to four years. With a bit of luck, you’ll be decorating your Norfolk Island pine as a gorgeous living Christmas tree for years to come. Just be sure to choose one with enough room underneath for the multitude of presents Santa will bring (provided you’ve been good, like me).