Protect Your Arborvitae: A Comprehensive Guide to Winter Cover
Arborvitae, known for their lush green foliage and elegant columnar shape, are a popular choice for hedges, privacy screens, and ornamental landscaping. While relatively hardy, these evergreen conifers can suffer damage during harsh winters. Heavy snow, ice storms, and strong winds can break branches, deform their shape, and cause browning or desiccation (drying out). Therefore, providing proper winter protection is crucial to maintaining the health and beauty of your arborvitae. This comprehensive guide will walk you through everything you need to know about covering your arborvitae for winter, from assessing their needs to choosing the right materials and implementing effective techniques.
## Why Cover Arborvitae for Winter?
Before diving into the how-to, let’s understand why winter protection is so important for arborvitae. Several factors contribute to the potential for winter damage:
* **Heavy Snowfall:** Accumulating snow can weigh down branches, causing them to bend, break, or splay outwards, ruining the plant’s shape. Young or newly planted arborvitae are particularly vulnerable.
* **Ice Storms:** A coating of ice adds tremendous weight to branches, making them even more susceptible to breakage. Ice can also suffocate the foliage.
* **Strong Winds:** Winter winds can desiccate evergreen foliage, leading to browning and dieback. This is especially true in areas with low humidity and exposed locations.
* **Salt Damage:** If you live in an area where salt is used for de-icing roads and sidewalks, salt spray can damage or kill arborvitae needles.
* **Sun Scald:** While it might seem counterintuitive, the winter sun can also cause damage. On sunny days, the sun can warm the needles, causing them to lose moisture. If the ground is frozen, the roots can’t replenish this moisture, leading to sun scald.
By covering your arborvitae, you can mitigate these risks and ensure they emerge from winter healthy and vibrant.
## Assessing Your Arborvitae’s Needs
Not all arborvitae require the same level of winter protection. Consider the following factors when assessing your plants’ needs:
* **Age and Size:** Young, newly planted arborvitae are more vulnerable to winter damage than established, mature trees. Smaller plants are also more easily covered. Larger, mature arborvitae might only need protection in exceptionally harsh winters or if they are particularly susceptible to snow or ice damage.
* **Variety:** Some arborvitae varieties are naturally more cold-hardy and resilient than others. Research the specific variety you have to understand its cold tolerance and susceptibility to winter damage. For example, ‘Emerald Green’ arborvitae is generally considered to be quite hardy, while more sensitive varieties might require more protection.
* **Location:** Arborvitae planted in exposed locations, such as on a windy hillside or near a road where they are exposed to salt spray, will need more protection than those planted in sheltered locations.
* **Recent Planting:** If you’ve recently planted your arborvitae, providing winter protection for the first one or two winters is highly recommended to help them establish their root systems.
* **Previous Winter Damage:** If your arborvitae have experienced winter damage in the past, such as broken branches or browning foliage, it’s a good idea to take preventative measures.
Carefully consider these factors to determine the appropriate level of winter protection for your arborvitae.
## Choosing the Right Materials
The type of materials you use to cover your arborvitae will depend on the size of the plants, the severity of the winter weather in your area, and your personal preferences. Here are some common options:
* **Burlap:** Burlap is a natural, breathable fabric that provides excellent protection from wind and sun. It allows air circulation, preventing moisture buildup and reducing the risk of fungal diseases. Burlap is readily available in rolls or pre-made wraps.
* **Anti-Desiccant Sprays:** These sprays coat the foliage with a waxy substance that helps to reduce moisture loss. They are effective in preventing winter burn, especially in windy areas. Apply according to the manufacturer’s instructions, typically in late fall before the ground freezes.
* **Evergreen Anti-Transpirant:** Similar to anti-desiccant sprays, these products create a protective barrier on the foliage, reducing water loss. They can be particularly helpful for newly planted arborvitae or those in exposed locations.
* **Snow Fences or Windbreaks:** These physical barriers can help to protect arborvitae from strong winds and drifting snow. They are particularly useful in areas with heavy snowfall.
* **Twine or Soft Rope:** Twine or soft rope can be used to gently tie up the branches of arborvitae, preventing them from splaying outwards under the weight of snow or ice. Avoid using wire, as it can damage the bark.
* **Shrub Covers:** Pre-made shrub covers made from breathable fabric or mesh are available in various sizes. These covers offer convenient and effective protection from wind, sun, and snow.
* **Stakes:** Wooden or metal stakes can be used to support young arborvitae and prevent them from being bent or uprooted by strong winds or heavy snow.
* **Mulch:** A layer of mulch around the base of the plant helps to insulate the roots and retain moisture.
Consider the pros and cons of each material before making your selection. Burlap is a good all-around choice, while anti-desiccant sprays are effective for preventing winter burn. Snow fences or windbreaks are ideal for areas with heavy snowfall. Choose the materials that best suit your needs and budget.
## Step-by-Step Guide to Covering Arborvitae for Winter
Here’s a detailed step-by-step guide to covering your arborvitae for winter, incorporating different methods and materials:
**Step 1: Preparation (Late Fall)**
* **Water Deeply:** Before the ground freezes, water your arborvitae deeply. This will help to hydrate the roots and prepare the plant for winter.
* **Apply Mulch:** Add a 2-3 inch layer of organic mulch, such as wood chips or shredded bark, around the base of the plant. Keep the mulch a few inches away from the trunk to prevent rot.
* **Prune Lightly:** Remove any dead, damaged, or diseased branches. Avoid heavy pruning in the fall, as this can weaken the plant.
* **Clean up Debris:** Remove any fallen leaves or other debris from around the base of the plant to prevent the buildup of moisture and pests.
**Step 2: Applying Anti-Desiccant Spray (Late Fall – Before First Freeze)**
* **Choose a Day with Favorable Weather:** Select a day that is dry and mild, with temperatures above freezing. Avoid spraying on windy days, as the spray can drift.
* **Read the Instructions Carefully:** Follow the manufacturer’s instructions for application rates and safety precautions.
* **Apply Evenly:** Use a pump sprayer to apply the anti-desiccant spray evenly to all surfaces of the foliage, including the undersides of the needles. Ensure complete coverage for optimal protection.
* **Allow to Dry:** Allow the spray to dry completely before the first frost or snowfall.
**Step 3: Tying Up Branches (Late Fall – Before Heavy Snow)**
* **Choose a Mild Day:** Select a day that is dry and mild, with temperatures above freezing.
* **Use Soft Twine or Rope:** Use soft twine or rope to gently tie up the branches of the arborvitae, starting from the bottom and working your way up. The goal is to reduce the spread of the branches and prevent them from splaying outwards under the weight of snow or ice.
* **Avoid Over-Tightening:** Do not tie the branches too tightly, as this can damage the bark and restrict air circulation. The branches should be tied loosely enough to allow for some movement.
* **Create a Cone Shape:** Aim to create a more compact, cone-like shape. This will help to shed snow more easily and reduce the risk of branch breakage.
* **Secure the Top:** Secure the top of the plant by tying the twine or rope around the topmost branches.
* **Check Periodically:** Throughout the winter, check the twine or rope to ensure that it is not too tight and that the branches are not being damaged. Adjust as needed.
**Step 4: Wrapping with Burlap (Late Fall – Before Heavy Snow)**
* **Measure the Plant:** Measure the height and circumference of the arborvitae to determine the amount of burlap needed.
* **Wrap the Plant:** Starting at the base of the plant, wrap the burlap around the trunk and branches, overlapping each layer slightly. Ensure the burlap is securely fastened to the plant.
* **Secure the Burlap:** Use twine or burlap staples to secure the burlap in place. Start at the bottom and work your way up, overlapping each layer to provide complete coverage.
* **Create a Cylinder or Cone Shape:** As you wrap, form the burlap into a cylinder or cone shape, depending on the natural shape of the arborvitae.
* **Leave the Top Open (Optional):** In some cases, you may choose to leave the top of the burlap wrap open to allow for better air circulation. However, if you live in an area with heavy snowfall, it’s best to cover the entire plant to protect it from the weight of the snow.
* **Alternative Method – Burlap Squares:** If you’re covering a smaller Arborvitae, you can use square pieces of Burlap. Wrap these around the tree like you’re applying shingles, securing them with twine as you go. Overlap each piece by at least 50% to provide good coverage and insulation.
**Step 5: Installing a Snow Fence or Windbreak (Late Fall – Before Heavy Snow)**
* **Position the Fence:** Place the snow fence or windbreak on the windward side of the arborvitae, typically the north or west side. The fence should be tall enough to provide adequate protection from the wind and snow.
* **Secure the Fence:** Secure the fence to sturdy posts or stakes, ensuring that it is stable and will not be blown over by strong winds.
* **Maintain a Distance:** Position the fence a few feet away from the arborvitae to allow for air circulation and prevent the accumulation of snow directly against the plant.
**Step 6: Staking (If Necessary – Especially for Young Trees)**
* **Drive Stakes into the Ground:** Drive two or three sturdy stakes into the ground around the arborvitae, a few feet away from the trunk.
* **Attach the Tree to the Stakes:** Use soft twine or rope to attach the tree to the stakes. Do not tie the tree too tightly, as this can restrict growth and damage the bark. Allow for some movement to prevent the tree from becoming too rigid.
* **Check Periodically:** Throughout the winter, check the stakes and ties to ensure that they are secure and that the tree is not being damaged.
**Step 7: Monitor and Maintain Throughout the Winter**
* **Check Regularly:** Check your covered arborvitae regularly throughout the winter, especially after heavy snowfalls or ice storms.
* **Remove Excess Snow:** Gently remove any excess snow from the burlap or branches to prevent them from breaking or bending. Use a broom or soft brush to avoid damaging the foliage.
* **Adjust Burlap as Needed:** If the burlap becomes loose or damaged, adjust or repair it as needed.
* **Look for Signs of Damage:** Watch for signs of winter damage, such as browning foliage or broken branches. If you notice any damage, prune away the affected areas in the spring.
* **Water on Thaw Days:** If there are prolonged periods of thaw during the winter, water your arborvitae deeply to help replenish moisture lost to transpiration.
## Removing Winter Protection
The timing of removing winter protection is crucial. Remove the coverings too early, and your arborvitae may be vulnerable to late-season frosts or winds. Remove them too late, and you could create a humid environment that encourages fungal diseases.
* **Wait for Consistent Warming:** The best time to remove winter protection is in early spring, after the danger of severe frosts has passed and when temperatures are consistently warming. A good indicator is when other plants in your area are starting to show new growth.
* **Choose a Cloudy Day:** Remove the coverings on a cloudy day to prevent the plants from being shocked by sudden exposure to bright sunlight. This is especially important if the arborvitae has been heavily covered.
* **Remove Gradually:** If you have used burlap or other wraps, remove them gradually over a period of a few days. This will allow the plants to acclimate to the changing conditions.
* **Inspect the Plants:** After removing the coverings, inspect the plants for any signs of damage or disease. Prune away any dead or damaged branches and apply a fertilizer if needed.
## Troubleshooting Common Problems
* **Browning Foliage (Winter Burn):** This is a common problem caused by desiccation. Ensure that your arborvitae are well-watered in the fall and that you have applied anti-desiccant spray or wrapped them with burlap. Make sure to water on thaw days if possible.
* **Broken Branches:** This is usually caused by heavy snow or ice. Tie up the branches of your arborvitae before winter to prevent them from splaying outwards. Gently remove excess snow after heavy snowfalls.
* **Fungal Diseases:** These can occur in humid conditions, especially under wraps that don’t allow for adequate air circulation. Use breathable materials like burlap and ensure that the coverings are not too tight. If you notice signs of fungal disease, apply a fungicide according to the manufacturer’s instructions.
* **Salt Damage:** If you live in an area where salt is used for de-icing, protect your arborvitae from salt spray by using a snow fence or windbreak. You can also rinse the foliage with water after exposure to salt spray.
## Conclusion
Covering your arborvitae for winter is an essential step in protecting these valuable landscape plants from the damaging effects of harsh weather. By carefully assessing your plants’ needs, choosing the right materials, and following the steps outlined in this guide, you can ensure that your arborvitae emerge from winter healthy, vibrant, and ready to thrive. Remember to monitor your plants throughout the winter and take corrective action as needed. With a little preparation and effort, you can enjoy the beauty of your arborvitae for many years to come.