Henry Homeyer: Are living Christmas trees a good idea?

By Henry Homeyer
©2019 Telegraph Publishing LLC

I know people who say we shouldn’t be cutting down trees just to brighten our homes for the holidays. Trees are, after all, sequestering carbon and making our environment cleaner, greener, and all that.

I disagree and will cut a fresh tree from my neighborhood tree farmer. I say Christmas trees are a crop like corn: planted, then harvested and then more are planted the next year.

If you want to have a live tree inside the house and plant it outside afterward, you can. I’ve never done it, but I’ve talked to people who have. Here’s what I’ve learned:

First know that chances of survival are only 50-50 or thereabouts. Planting a tree in New England in January is not easy. For starters, the ground will probably be frozen. Keeping a tree hydrated and happy in the house is a challenge, even for an attentive tree steward. But let’s see how you can improve your odds.

If you want success, you have to think small. A six-foot tree will have a big, heavy rootball, and will be harder to move and harder to plant. Think three to four feet tall, maximum, and even smaller if you can. The best is a tabletop tree.

Buy a fir or spruce that has been grown in a plastic container, not one that is recently dug up or wrapped in burlap. Place the tree in the coolest part of the house – and never near a radiator or woodstove.

I suggest that you think where the tree will be planted after the holidays before you buy one. Too many times I’ve seen a huge blue spruce towering over a nice little ranch house, blocking out the sun from the big picture window. This is because the tree was small and cute when the owner of the house planted it, and he never thought about its ultimate size.

Balsam fir (Abies balsamea) is one of the classic Christmas trees. In the wild it will grow to be 45 to 75 feet tall with a spread of 20 to 25 feet. This is not the tree to place close to the house. There are a few cultivars that are supposed to stay small, but mostly such trees just grow slower than the standard varieties. In 40 years, a dwarf may no longer be a dwarf.

Blue spruce (Picea pungens) is another good-sized tree in the wild, 30 to 60 feet tall with a spread of 20 to 30 feet. There are spruce that stay small, I have read. ‘Blue Kiss’ is one that, after 40 years growing in Ohio, is reported to be only 8 feet tall and 10 feet wideBut that’s still enough to block most windows. So choose the location well. ‘Fat Albert’ is one that is designed to stay low and wide.

One thing you could do to keep the ground from freezing solid would be to buy a bale of hay or straw now and use it as insulation. Just spread a thick layer of it over the soil at the site where you will plant your tree. Between now and January it is likely we will have some very cold days. And unless we have a thick layer of snow, the top few inches of soil can be frozen solid by the time you want to plant your tree outdoors. Yes, you can break up frozen soil with a pick ax, but do you want to? Or you can dig the hole when you buy your tree.

I would also buy a few bags of topsoil now and store them in a warm basement. Then if the soil is frozen when it’s time to plant, and you hack out a hole, you can backfill the hole with soil that is not in frozen chunks. You will want some bark mulch or wood chips to spread over the soil once the tree is planted, too.

Instead of keeping a live tree in the house for a month, the way many of us do with cut trees, think about having it indoors for just a week or 10 days. That will reduce the stress on the tree considerably. Keep the soil lightly moist, but not soggy.

When the time comes to plant your tree, be sure that you dig the hole the appropriate depth. Never plant a tree in a hole that is deeper than necessary. Look for the trunk flare, that part of the tree that would be above ground if growing in the wild.

Keep the trunk flare above ground and do not cover it with bark mulch. To do so is to consign your tree to an early death. The bark will rot if covered with soil or mulch, and the tree will decline in 6 to 10 years. Many trees come in the pot with the trunk flare covered with soil, so you may have to expose it when you plant. And don’t forget to water your tree after you plant it, even if it is below freezing outdoors.

One nice thing about buying a cut tree that reaches the 10-foot ceiling in my house is this: after the holidays I will cut off all the branches and use them to provide some protection for less hardy plants that might be harmed by cold winter winds. I will layer them over perennials that are “iffy” in my climate, or use them to protect roses or other shrubs that might be damaged by the cold.

So go ahead and buy a live tree for the house if you wish, but please don’t hold your nurseryman responsible if your tree doesn’t survive the winter.