What is winter burn?
Winter burn is what happens when the leaves of a plant dry out and are damaged.
This occurs when the amount of water lost through the leaves is greater than the amount of water the roots can take up. This is most evident in evergreens during the winter season; the ground is frozen in winter, and the plants cannot absorb water – yet water is still being lost from the leaves. As a result, the foliage starts to dry out and become brittle. Dry, cold winds further intensify the problem.
By late winter you may start seeing significant browning on many of your evergreens, particularly those most exposed to the wind and cold.
Damaged Plants: What can be done?
Don’t panic just yet, most plants are not permanently damaged. Healthy new growth will push out damaged foliage in spring. At which point, the following treatments can be applied:
- Once the ground has thawed, water the plant well and continue to water regularly throughout the growing season.
- Fertilize in spring with Plant-tone or Holly-tone.
- Apply mulch around the base of the tree – no more than 2″ and never mound it up against the trunk.
- Rake up any leaves that have fallen – this is important otherwise they can grow and carry fungus spores that will spread to the plant.
- Prune and remove branches that are completely dead.
How can you prevent it?
- Keep evergreens watered until the ground freezes. This is especially true of new plantings – if you’re planting late in the season, you need to be able to access the plant and keep it watered after the irrigation system is turned off.
- Install new plantings a month prior to the ground freezing to give the roots time to establish before winter, particularly if planting in exposed areas.
- Apply mulch around the base of evergreens to retain moisture throughout the growing season. As the mulch breaks down, the organic matter will increase your soil’s water holding capacity.
- Apply a granular fertilizer in the fall, such as Holly-tone or Plant-tone
- Protect new and exposed evergreens by wrapping them in burlap after applying an anti-desiccant spray in late fall.