LISLE, Ill. (Nov. 21, 2023)— As shopping for live Christmas trees gets underway this holiday season, the tree experts at The Morton Arboretum recommend choosing one carefully and caring for it properly to ensure it stays fresh through the season.
“People often buy live evergreen trees long before Dec. 25,” said Spencer Campbell, the Arboretum’s Plant Clinic manager. “A tree that is not cared for can dry out and become a fire hazard. A well cared for tree, with a constant water supply, should remain green and fragrant for several weeks, well through the holidays.”
The Arboretum’s Plant Clinic provides free advice by phone or email for those with questions about how to care for trees and plants, including Christmas trees. Whether tree shoppers intend to have theirs up for six weeks or one week, Campbell offers these recommendations for keeping trees fresh.
1. Plan for watering. A cut evergreen tree needs water like flowers in a vase. Vessels where water flows are right under the tree’s bark, so it’s important to keep the bark undamaged. Tree stands should hold at least a gallon of water.
2. Choose a tree that will fit in the stand. Never try to whittle down the trunk to fit a too-small stand. Doing so will destroy the water vessels under the bark so the tree can’t take up water, and it will quickly dry out. Bring the stand to the tree lot to ensure the chosen tree fits.
3. Buy a fresh tree. A more recently cut tree will provide greater time to enjoy it before it dries out and becomes a hazard. The freshest tree is one cut at the time of purchase from a choose-and-cut tree farm. Trees from small local lots are likely to have been harvested within a few days or weeks, making them fairly fresh. Wherever a tree is purchased, check it carefully for freshness.
4. Test for green, firm, flexible needles. To judge whether a tree is fresh, use a hand to gently brush a branch. If many needles fall off or if the needles feel stiff or crackly, the tree is dry and should not be bought. Needles on a fresh tree are plumped with water. They should be firmly attached, pliable and fragrant. It’s normal for an evergreen in autumn to lose some yellow or brown needles, but dropping a significant number of green needles is an indication the tree is drying out. Don’t buy a tree if the seller won’t let the customer unwrap it to examine its freshness.
5. Select a suitable species. Some evergreen species dry out more slowly and keep their needles longer than others. Needle types and branching forms also differ. Some types of trees have soft, bendy branches, while others have stiff branches that can support heavy ornaments. Among the species sold most often in the Chicago area are Fraser fir, balsam fir, concolor fir and Scots pine. Learn more about different kinds of Christmas trees on The Morton Arboretum website.
6. Make a new cut. When an evergreen’s trunk is cut, sap quickly dries and seals the surface. To open the tree to water, cut off about an inch from the bottom, or ask for that to be done at the tree lot. Place the tree in water within about an hour after it’s cut to prevent sap from sealing the trunk again.
7. Store a tree in water. If a tree will be kept outdoors before being set up inside, place it in a bucket of water in a sheltered spot or in an unheated garage. Top off the water in the bucket daily.
8. Keep the tree far from heat. Once it’s set up indoors, position the tree well away from heat sources such as a radiator, heating vent or fireplace. Even a very sunny window can dry out a tree. Place the tree stand on a waterproof surface, such as a plastic tarp, to protect carpeting or wood floors.
9. Fill it up. As soon as the tree is in place, fill the stand with warm tap water. Check the water at least twice daily and refill as necessary. Never allow the water level to fall below the bottom of the trunk. If the cut surface is exposed to air and seals with sap, the tree will not be able to absorb any more water.
10. Use plain water. Don’t add aspirin, sugar or any other substance. Water is all the tree needs.
11. Decorate with lights that stay at a cool temperature. Older incandescent tree lights run hot. Newer LED lights not only use much less energy, but because they are more efficient and cooler, they don’t dry out a tree nearly as much.
12. Keep checking for freshness. It’s normal for a tree to lose a few needles every day. If it begins to lose many needles and the branches become brittle, the tree has dried out. Remove it from the house for safety’s sake.