Q. I have always enjoyed having a live Christmas tree, but have had problems the last few years with the trees dropping their needles to the point where I am considering getting an artificial tree. Before I do that, I wondered if there was anything I could do to minimize problems with excessive needle drop.
A. There are a number of factors that affect how well cut Christmas trees retain their needles, including kind of tree, growing conditions in the year it was harvested, and how it has been stored since it was harvested.
Although people have their own favorite kinds of cut Christmas trees, Frasier and balsam firs and Douglas-firs have good reputations for needle retention. If you prefer pines, Scotch and white pines also rate high for good needle retention.
However, even those species may not hold their needles as well if they have been harvested after suffering severe drought stress through the growing season. Once Christmas trees have been harvested, it is best if they are kept cool and sheltered from direct sun and strong winds.
Cutting your own tree from a local Christmas tree farm is the surest way to get a fresh tree. While this is a cherished family tradition for many, the convenience of purchasing a pre-cut tree is more attractive for others.
When you shop for a pre-cut tree, look for flexible needles that remain firmly attached to the stem when you tug on them. All needled evergreens shed their oldest needles every year, so do not be concerned when brown needles fall from the interior of the tree when you knock the base of the tree on the ground. Just make sure they are thoroughly shaken off the tree before taking it indoors. If the needles pull out or break easily, or if they appear a dull, lifeless green, that tree may be past its prime.
If you need to hold the tree for a few days before putting it up indoors, keep it in a sheltered area out of direct sun and wind – perhaps an unheated garage, or the north or east side of your house, preferably in a container of water to keep it fresh. Make a new cut about one-quarter inch deep across the base of the trunk to open fresh vascular tissue. The cut should be straight across so the tree sits properly in the stand. Also, try not to damage the bark on the trunk too much. A tree’s vascular system is right under the bark, and it is important to keep it as intact as possible so that the tree can absorb water freely.
Once you have a fresh cut on the base, place the tree in a bucket, tree stand or other container of water and make sure the base of the trunk is always submerged. If the base of the tree does dry out and seal up, you will have to re-cut the base to allow it to absorb sufficient water.
When you take it indoors, remember that cooler temperatures and higher humidity will prolong the life of the tree. If possible, close heat vents in that room to keep it cooler. Keep the tree as far away as possible from heat vents, fireplaces, and out of south and west windows that receive the strongest sun.
Make sure your tree stand holds at least one gallon of water, and a larger reservoir is even better. Cut trees use about a quart of water per inch of trunk diameter a day, and the water must always cover the base of the tree. Although the tree will use the most water during the first week indoors, be sure to check it daily and add water as needed as long as it is up.
Be sure the water level is up over the base of the tree. If the base is allowed to dry for six hours or so, the sap will seal off the vascular system and you will need to recut the base, something that may not be easy once the tree has been decorated. You do not need to add anything to the water – there is no evidence that adding aspirin, sugar or Christmas tree preservative extends the life of cut trees better than plain water.