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Ah, December, the month when many people bring a little -- or not-so-little -- piece of the great outdoors inside in the form of a Christmas tree. But what kind of care does a felled tree need to look and smell its best for the (purportedly) most festive weeks of the year?
Fortunately, Christmas trees are pretty low-maintenance during their holiday foray indoors. "We treat the trees like a cut flower, basically," says Justin Whitehill, a plant pathologist who researches Christmas trees full time at North Carolina State University. "You don't need to complicate it."
To that end, he says, skip the additives that people may try to sell you, and ignore any rumors you hear about giving your tree sugar water or aspirin -- plain tap water is all it needs, although Whitehill admits to encouraging people to give their tree "fresh, cold water just because it sounds refreshing for the tree." (Keeping a Christmas tree well-watered is botanically wise but also extremely pragmatic, given that holiday trees caused an average of 155 home fires a year in the U.S. between 2018 and 2022. These fires are often serious because of a dried tree's flammability.)
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Christmas trees are particularly thirsty when they first come inside and are still adjusting to no longer having roots in the ground. "The first day or two, it'll drink several liters of water," Whitehill says. From there, its appetite will subside, he says. "Eventually you won't need to water it as much." Fortunately, all a black-thumbed Christmas tree tender needs to do is make sure to keep an eye on the water level in the tree's stand: just keep it topped up, and the tree will take care of itself, Whitehill says.
One quick step before you install your tree can also help it thrive: cut off the bottom half inch or inch of the trunk. "When you get a tree, you want to make sure that you have a fresh cut," Whitehill says. "That's going to sort of open up the vascular system," which are the pipes that move water, sugar and nutrients throughout a tree. That helps the tree take in more of the water it's given.
Another small measure that can keep your tree in good condition is to keep it in a relatively cool part of your home, Whitehill says, because warm temperatures can make the tree dry out and lose its aromatic compounds faster. (This is why the stereotypical spot next to the fireplace isn't usually the best choice, fire risk aside.)
Unfortunately, if your most common pet peeve surrounding Christmas trees is that they drop needles, there's no specific care approach that can help, Whitehill says. How well a tree hangs onto its needles tends to vary by species -- Christmas trees can hail from a range of conifer species -- and individual genetics. For example, Fraser firs tend to hang onto their needles well, whereas many pines drop their leaves more quickly.
But that's not a reason to get too fixated on what species your tree might be, Whitehill says -- especially because the species of a Christmas tree is often unlabeled or mislabeled. (It can also be tricky to identify correctly, he says, although he encourages the curious to try.) In his expert opinion, an individual's connection with a farmed tree is far more important than its species. "As long as you like the tree," Whitehill says. "Every tree needs love."