Do I need to wrap my tree’s trunk in the winter?
We recommend trunk wrapping for young trees—as long as you follow the wrapping guidelines! Sadly, improper wrapping is a common cause of young tree death. That’s because young trees are susceptible to sunscald and frost cracks due to drastic winter temperature fluctuations. To prevent bark damage, be sure to wrap the trunks of younger trees up to the first branches using commercial, brown paper tree wrap, available at home improvement stores or online (don’t use plastic or fabric!). A general rule of thumb is to wrap the trees around Thanksgiving and remove the tree wrap around Easter. Just don’t forget to remove the tree wrap in the spring! New trees should be wrapped for their first three winters after installation.
CSU Extension shows you how to properly wrap a tree for the winter.
Do I have to keep mulch around the base of the tree?
Yes. Applying mulch is the best way to protect your tree and give it the nutrients that it requires. Apply wood chips, bark or other organic mulch 2 to 4 inches deep in a ring around the base of the tree, but at least 3 inches away from its trunk. Mulch reduces soil evaporation, improves water absorption, insulates against temperature extremes and can break down over time, adding necessary nutrients to the soil. Make sure to replenish your mulch at least a few times a year. Avoid other types of mulch, especially rocks, as they can interfere with healthy tree establishment and growth. Some recycling programs like Denver Recycles provide wood chips free of charge.
Do I need to stake my tree?
Generally, no. Staking can cause weaker trunks and less–developed root systems. We only recommend staking if your tree will not stand straight on its own, because it’s in a high wind area or was planted in extremely loose soil. Use wide, flat straps to attach trees to stakes. Don’t use wire, string, rope or rubber hose around a tree. These structures can girdle, or “strangle” a growing tree, prohibiting the tree from transporting the water and nutrients it needs, eventually causing tree death. Remove stakes and straps after roots are established, usually after one or two growing seasons. Learn about staking trees from the University of Minnesota and planting and caring for trees from CSU. You can buy all necessary staking material at your local nursery or hardware store.
Important things to remember when staking:
- Use soft materials against the bark of the tree to protect it during this time. No twist-ties, wires, zip-ties or thin string that can cause cuts and abrasions to the bark.
- Allow your tree to have some sway, so don’t stake it too tight. This can help it grow the proper array of stabilizing roots to remain sturdy for the rest of its life.
- Make sure the staking helps the tree stand straight. It doesn’t help if you stake the tree in the wrong direction, pulled to one side.
- Do not leave the staking material on for more than two years as this can cause the tree to rely on staking to remain stable.
Should I prune my tree?
It depends. During the first three years of your tree’s life, prune only dead, damaged or diseased branches. You can also remove suckers—shoots that grow at the base of the tree—and branches that cross and rub one another, to ensure proper vertical growth. Many species in Denver have specific pruning constraints, so it’s important to understand pruning tips and tricks or work with a licensed tree care professional. If you need to learn more prior to pruning, reach out to Denver’s Office of the City Forester with questions, concerns or just to get more information at forestry@denvergov.org.
How long will it take for my tree to establish?
Great things take time! During the establishment phase, the tree will focus more on its root system and have minimal canopy growth. However, with correct planting technique, good soil conditions and proper watering, tree establishment takes one growing season per inch of trunk diameter. We typically plant 1.5– to 2-inch caliper trees that stand about 8 feet tall, so establishment will likely take 2-3 years under ideal conditions. Tree establishment may take longer with improper planting techniques, improper tree maintenance and/or poor soil conditions—which makes it all the more important to ensure you’re caring for your new tree properly!
Learn more about tree establishment and tree care during the establishment phase from CSU Extension.
How do I care for my established/mature tree?
It’s important to take care of our trees at all stages of their life—from when they’re first planted through our free trees program and for all the years that follow. Luckily, there are many resources out there that provide everything you need to know on how to be a good tree owner. You can read up on how to provide water and nutrients to your mature trees, manage any damage or prune them appropriately. Our friends at CSU Extension have helpful resources on how to care for many types of trees and shrubs. And finally, our partners at The Park People outline what you need to know about caring for trees at each growth stage.