Arborvitae (Thuja) is one of the most adaptable and visually appealing trees and shrubs in the landscape. They provide excellent hedge material, container plants, and unique focus pieces for the landscape. This easy-to-grow evergreen is available in a broad range of sizes and hues, making it suitable for nearly any landscape environment. With a few simple instructions on how to cultivate arborvitae, you’ll have a plant with an exceptional growth habit and low maintenance requirements. But with that, you also need to know the tips to prevent Arborvitae turning brown. Take a look.
Thuja can turn brown in the winter due to wind, sun, freezing temperatures, and a lack of proper water (as well as the leaves of other evergreens). As a result of their evaporation, this happens. When an evergreen shrub’s root system is unable to pull water up to its leaves during periods of ground freezing (during which any moisture in the soil is unavailable), the leaves, which are already stressed, lose their green color and Arborvitae turns brown.
On this page:
- Facts About Arborvitae
- Conditions for Arborvitae Growth
- Arborvitae Propagation
- When to Plant Arborvitae?
- Arborvitae Browning
- How to Save Brown Arborvitae Trees?
- Arborvitae Turning Brown: Conclusion
Facts About Arborvitae
Arborvitae was the first tree species from North America to be brought into Europe. It is also known as white cedar of the north, white cedar of the east, and swamp cedar. Over 1,000 years old is the oldest arborvitae species.
Native Americans make use of the roots to weave baskets and the leaves to make tea. The timber is used to build log homes, fence posts, shingles, paneling, boats, and other woodworking projects.
Conditions for Arborvitae Growth
Arborvitae thrives in well-drained and wet soil that receives full sun or even partial shade. The majority of the United States’ zones provide optimal growth conditions for arborvitae, which are hardy to USDA Zone 3. Before planting arborvitae, check drainage and apply grit to a depth of 8 inches (20.5 cm.) if your soil holds excessive moisture. Arborvitae requires a soil pH of 6.0 to 8.0, which must contain a significant amount of organic matter in order to improve its composition and nutritional levels.
Late summer or autumn is the best time to pick up stem cuttings. The steps for Arborvitae Propagation are as follows:
- Take 4 to 5-inch cuttings from the current branch growth.
- Remove the leaves from the lower part of the cut.
- Fill a small bowl in the middle of a mixture of live soil or a mixture of sand-peat moss.
- Immerse the cutting in rooting hormone and then place it in the container.
- Fill the pot with water and cover it with a clear plastic dome or wrap.
- Place the pot in a place that receives filtered light.
- If the soil becomes dehydrated, re-hydrate it. The roots will develop in around 6 to 8 weeks.
- Discard the protective plastic.
- Increase the size of the container by adding dirt and in the next spring, transplant outside.
When to Plant Arborvitae?
To get the optimum effects, the majority of evergreen plants, such as arborvitae, are planted in the dormant stage. They can be planted in late winter if the soils are workable, or in early spring once the ground has thawed. Arborvitae is usually sold with a balled and bur lapped, which protects the root system in difficult conditions and allows you to plant arborvitae earlier than empty trees. They can also be planted in the ground in late autumn if a hard layer of bark or organic mulch is used to cover the roots.
You might wonder “why is my arborvitae turning yellow?”. It is not uncommon for Arborvitae turning brown during the colder months. Let’s look at the common reasons for newly planted arborvitae turning brown.
Reasons for the Arborvitae Turning Brown
Arborvitae leaves can turn brown at any time of year. When this occurs during the summer, it is possible that the hue shift is caused by drought. However, if your arborvitae shrub becomes dark in the winter or early spring, winter burn is most likely the cause. Wind, sun, cold temperatures, and a lack of adequate water throughout the winter can cause Arborvitae turning brown (as well as the leaves of other evergreens). This occurs as a result of their evaporation. When an evergreen shrub is unable to pull water up through its root system to its leaves during times of ground freezing (during which any moisture in the soil becomes inaccessible), the leaves, already under stress, lose their green hue and results in Arborvitae turning brown.
Arborvitae That Has Been Newly Transplanted Maybe in Shock
If your newly planted arborvitae trees are yellowing, browning, or withering at the tips, the most likely reason is transplant shock. Due to the fact that these evergreens frequently lose a significant portion of their roots when dug up at the nursery, they will require time to establish more roots and will likely continue to appear unhappy until they do. As a result, you’ll want to minimize their tension during the changeover phase.
Plant arborvitae in the spring or early fall for the greatest results, spreading the roots out carefully rather than tearing them apart. Arrange the plants in such a way that the tips of their roots do not appear above the ground, and water them well and consistently for the first six months after planting. Do not alter their backfill with amendments and wait a year before fertilizing them.
Newly Planted Arborvitae Turning Brown Might be a Symptom of Winter Burn
Due to decreased chlorophyll levels in the winter, the colour of an evergreen shrub is frequently “bronze”. If the browning leaves on your arborvitae do not appear to be dry, it may take on a reddish color that will recede on its own in the spring when chlorophyll production begins again.
If, on the other hand, the foliage appears to be withering, the issue is most likely a burn. This can be caused by a multitude of factors, including extreme cold or excessive sunlight, which can dry out the visible portion of the plant while the roots remain too frozen to restore the liquid lost.
To avoid this, water your shrubs in late fall, just before freezing conditions set in, and mulch them with around 3 inches of shredded bark. Additionally, you may shield them from the elements by surrounding them with a burlap screen or a burlap cover throughout the winter.
How to Save Brown Arborvitae Trees?
Wrap Arborvitae with Burlap
Wrapping your arborvitae trees with burlap is an excellent technique to protect green giant arborvitae turning yellow over the winter. Burlap is a heavy, somewhat affordable cloth that may work wonders in the cold. When the tree is unable to obtain water, the burlap will stop the light from striking the tree. It is advisable to perform this task immediately before ground freezing. Take a huge piece of burlap and wrap it around the tree starting at the base and wrapping it all the way to the top. To secure the burlap, wrap it with twine again, this time starting at the top and working your way down. While the tree is unable to get water, this protective barrier will secure it.
When the Soil Freeze, Water the Tree
If you prefer not to cover your tree with burlap but wish to reduce arborvitae browning, keep an eye on the ground during the winter. Water can only reach the roots if the soil is sufficiently loose. This may be impossible if the earth hasn’t thawed. However, there are periods during the winter when the temperature warms up sufficiently to allow the ground to thaw out. This is the time of year for arborvitae irrigation.
Apply Garden Mulch
Applying garden mulch around your arborvitae is another preventative step for green giant arborvitae turning yellow. Winter heat is a matter of humidity, and the cover of the trees helps to keep the soil around the plant moist.
Prune When Required
The branches of Arborvitae whose leaves become dark (completely) due to winter burn may not grow back, but there is no reason to prune prematurely (you do not know), so wait until spring or summer before pruning. Only time will tell if your arborvitae branches recover from winter burn; little can be done to reverse the damage that results in Arborvitae turning brown. Rather than doing that, focus your efforts on minimizing future winter damage. If green growth does reappear on a winter-burned limb, trim the branch back to the point where the greenery appeared.
Arborvitae Turning Brown: Conclusion
Whether your arborvitae tree has completely died or is just beginning to do so, immediate action is critical. According to this guide, re-mulching will help down the death process and may even save your tree. Regardless of your location, avoid overwatering your arborvitae and place it in an area that receives adequate natural sunshine to prevent Arborvitae turning brown issues.
Another approach to salvage browning arborvitae is to put it in a warm cover to keep it from freezing further. If you don’t want to take a chance on freezing weather, we recommend taking your tree inside for the winter during the final week of fall to avoid arborvitae dead spots.
Some visual information that you can found useful