Planting Your Containerized Christmas Tree

Southwest Yard and Garden | by Marisa Thompson

Conifer seedlings are grown in tall cone-tainers to minimize
circling roots at the NMSU John T. Harrington
Forestry Research Center in Mora, NM.
(photo by M. Thompson)

Question:

We bought a live, potted Christmas tree this year. When and how should we plant it in our yard?

-          Tammy Z., Albuquerque, NM

Answer:

What a great way to add a beautiful evergreen to your home landscape and, in doing so, help our urban forest efforts. My backyard growing up in South Carolina had several Christmas trees planted in the yard, each a memory from holidays past. However, when we planted our Christmas Rocky Mountain juniper in Las Cruces some years ago, it did not make it very long. I now know that I was severely overwatering that poor, sopping tree. 😢 It never stood a chance.

To more fully answer your question, I searched the NMSU Extension Publications website (http://aces.nmsu.edu/pubs/) and found Guide H-421, “Buying aLiving Christmas Tree,” which you might find useful as it includes information about planting and general care.

I also called the Albuquerque Parks and Recreation City Forester, Joran Viers, whose first piece of Christmas tree advice was, “Don’t plant the ones without roots.”

Jokes aside, Viers said that it will probably take a few weeks to harden the tree off during the transition from inside to outside. Acclimatize it to outdoor life by taking it outside in the daytime in increasingly sunny spots, and bring it inside each night for a few weeks, until it has gotten used to the cold and the intense sunlight. The longer you keep it inside, the longer you will need to harden it off.

Viers added, “The key to planting potted evergreens is to look closely at the actual root structure as much as possible to find circling roots before you plant. If you see circling roots, find the spot where the root starts to turn and cut it below the turn.” Circling roots are a major problem with the containerized tree industry. At first, they may grow normally after planting, but eventually the knotted roots are likely to strangle each other and may kill the tree. 

After several years of slow decline, this 11-year old Arizona
cypress was finally removed. The culprit: this
severely knotted rootball that could have been
avoided if circling (also called spiraling) roots had been
properly cut at time of planting.
(photo courtesy of  Dr. Curtis Smith)

Exposed root is choking this tree after being container-grown.
(open source photo)

Spiraling root ball of dead Osage orange
tree. (photo courtesy of Dr. John Mexal)

Exposed circling root still in container.
(photo courtesy of Dr. John Mexal)

The roots of this dead tree were so badly knotted due
to being overgrown and root-bound while still
in the container, then planted without any
correction of those circling roots.
(photo courtesy of Dr. John Mexal)

It is important to take good care when planting and maintaining plants in our environment. As New Mexicans, we are well aware of our water limitations. I believe watering landscape plants can be a good use of our groundwater, but if—and only if—we are doing so wisely. Correctly watering a tree that is specifically suited to our climate is great, but watering a dying tree is a waste. Dr. Curtis Smith, retired NMSU Extension Horticulture Specialist, advised watching for windy days when plants are more prone to drying out if not watered properly, especially while still in the pot and the first few months after planting. Both Smith and Viers warned, however, that conifers do not like wet feet, so check the soil moisture with a finger before watering. I wish I had known that before drowning my juniper. Check back next week for more on best tree planting practices that might surprise you. In the meantime, start taking your tree outside in the daylight hours.

Somebody please make me a bumper sticker with my favorite tree quote: The best time to plant a tree was twenty years ago. The second-best time is today. #climatechange #climatehope

Email me your gardening questions at desertblooms@nmsu.edu or share them on social media @NMDesertBlooms!

For more local gardening information, visit the www.desertblooms.nmsu.edu and the NMSU Horticulture Publications page at http://aces.nmsu.edu/pubs/_h/.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, office: 505- 865-7340, ext. 113.