Protecting Evergreens from Winter Burn: Tips for Seacoast Gardens
Protecting Evergreens from Winter Burn: Tips for Seacoast Gardens
When winter sweeps across the Seacoast, gardeners in towns like Portsmouth, Rye, and North Hampton know that cold isn’t the only challenge. The combination of strong winds, intense sunlight, and dry air can take a toll on evergreens, leaving once-lush boxwood, arborvitae, and holly looking brown and brittle by spring. This damage, known as winter burn, is one of the most common issues for coastal landscapes in Zone 6b. The good news is that with a few preventive steps, you can protect your evergreens and help them emerge from winter looking as vibrant as they did in fall.
What Is Winter Burn?
Winter burn occurs when evergreens lose more moisture through their leaves or needles than their roots can replace. It’s especially common along the coast, where strong winds and salt-laden air increase dehydration. The frozen soil limits the plant’s ability to take up water, while winter sun and dry winds pull moisture out of the foliage.
The result is visible browning or yellowing of leaves — especially on the side facing prevailing winds. Boxwood, arborvitae, and rhododendron are particularly susceptible because their leaves and needles remain active all winter.
Why It’s Common on the Seacoast
The Seacoast’s winter climate makes evergreens work hard to survive. While the Atlantic Ocean helps moderate temperatures, it also brings steady wind and salty air. This combination draws moisture out of foliage and can even leave a salty residue on leaves, compounding stress.
In towns like Rye and Hampton, gardens often sit in exposed, breezy locations. Inland properties in Exeter and Stratham may not face salt exposure, but they experience stronger freeze-thaw cycles. These temperature swings can cause root stress and further limit water uptake.
Early Prevention Is Key
The best time to protect your evergreens from winter burn is before the ground freezes. Once soil temperatures drop below 40°F, roots can no longer absorb water efficiently. Start preparing in late October or early November by making sure your evergreens are well-hydrated.
Give them a deep, slow watering before the first hard frost. Focus especially on recently planted shrubs and trees, which have smaller, less-established root systems. A thorough watering helps the plant store moisture in its tissues, creating a reserve for the months ahead.
Mulching for Moisture and Insulation
Mulch is one of your simplest and most effective defenses against winter damage. Apply a two- to three-inch layer of organic mulch around the base of each plant, keeping it a few inches away from the trunk. Mulch helps regulate soil temperature, retain moisture, and protect roots from freeze-thaw cycles that can cause heaving.
On the Seacoast, where sandy soils drain quickly, mulch is especially important. Use shredded leaves, pine needles, or composted bark for best results. A layer of mulch applied in late fall can make a noticeable difference when the winds pick up in January.
Using Burlap Wraps for Wind Protection
Burlap wraps are a tried-and-true method for shielding evergreens from harsh winds and winter sun. They work by creating a barrier that slows moisture loss while still allowing air circulation.
To install, drive three stakes around the plant in a triangle or square shape, then staple or tie burlap to the stakes, forming a screen. Avoid wrapping the burlap directly around the foliage, which can trap moisture and cause mold. For hedges like arborvitae, create a windbreak on the windward side rather than wrapping each shrub individually.
In coastal towns like Rye and North Hampton, burlap screens are invaluable where salt spray from nearby roads or ocean air can compound winter stress.
Anti-Desiccant Sprays: A Helpful Supplement
Anti-desiccant sprays, also called anti-transpirants, form a thin, waxy coating on evergreen leaves to reduce moisture loss. These products can be especially effective for boxwood, holly, and rhododendron.
Apply an anti-desiccant on a mild, dry day in late fall when temperatures are above 40°F. It’s important to coat both the upper and lower leaf surfaces. One application typically lasts two to three months, though a midwinter reapplication may be helpful after heavy rain or snow.
Avoid spraying blue-needled conifers like Colorado spruce, as the coating can dull their natural color. If you’re unsure whether an anti-desiccant is right for your shrubs, consult your local gardening professional for guidance.
Pruning for Health and Balance
Proper pruning also plays a key role in preventing winter damage. Well-pruned evergreens are naturally more resilient, with better air circulation and balanced structure. Remove any dead, diseased, or crossing branches in late fall to reduce stress points where snow or ice might accumulate.
For boxwood and arborvitae, avoid heavy pruning after late August. Late-season cuts can encourage tender new growth that won’t harden off before winter. Instead, plan major shaping for late winter or early spring when plants are still dormant.
If your shrubs already show some winter burn from previous years, light corrective pruning in early spring can help stimulate new growth and restore their natural form.
Managing Salt Exposure
Along the Seacoast, salt can be as damaging as wind. Road salt spray often settles on evergreens near driveways or walkways, drawing moisture from foliage and soil. To minimize damage, rinse affected plants with fresh water after storms to wash off residue.
Consider using calcium magnesium acetate or sand instead of traditional rock salt for de-icing near plant beds. These alternatives are less harmful to soil and roots.
Seacoast Conditions
Every Seacoast property faces unique conditions — from open coastal winds in Rye to sheltered inland gardens in Exeter. Understanding these microclimates helps tailor protection methods. In exposed areas, prioritize physical barriers like burlap screens and extra mulch. In milder microclimates, focus on proper watering and anti-desiccant treatments.
The goal is to keep your evergreens hydrated, shielded, and resilient through the long winter ahead. A little attention now will ensure lush, green foliage when spring arrives again on the Seacoast.
Trust the Local Experts
At Seacoast Gardener, we specialize in fine gardening and plant care designed for the unique coastal environment of New Hampshire’s Seacoast and Southern Maine. From pruning and shrub care to seasonal maintenance and garden protection, our team knows how to help your landscape thrive year-round.
If you’d like help preparing your evergreens for winter, reach out to Seacoast Gardener for professional guidance and seasonal services. Together, we’ll ensure your garden weathers the winter beautifully and comes back strong in spring.
Contact Information:
Seacoast Gardener — (603) 770-5072 | www.SeacoastGardener.com
Expert Pruning — (603) 996-3867 | www.ExpertPruning.com