How to Protect Evergreen Perennials From Winter Burn. Wind, Sun and Dry Cold.
You know that crispy brown edge on Heuchera leaves in March?
That's winter burn. Most of it happens in February, and it isn't really the cold that does it. It's the wind and the sun.
The good news is that most of the prevention happens right now.
WHAT CAUSES IT
Evergreen leaves keep losing water all winter, especially on sunny, windy days. But when the ground is frozen, the roots can't pull up any water to replace it. The leaves dry out and brown at the edges.
THIRSTY LEAVES. FROZEN STRAW.
WHO'S AT RISK
- Heuchera, especially in sunny spots
- Bergenia
- Hellebores
- Lavender
- Christmas fern in exposed spots
- Anything planted this year, since its roots are still small
1. WATER NOW
This is the big one. Give evergreen perennials a deep soak before the ground freezes, especially if fall has been dry. A plant that goes into winter fully hydrated has a lot more to lose before it burns.
2. LET THE SNOW HELP
Snow is the best protection there is. It shades the leaves and keeps them out of the wind. Leave the grasses and seedheads nearby standing, since they catch and hold snow. You can also pile clean snow from the walkway over low evergreen perennials. Not from the driveway, though. Road salt is a whole other problem, and we'll get into it in December.
3. MULCH AFTER THE GROUND FREEZES
Once the top few centimetres of soil have frozen, add a loose layer of shredded leaves or evergreen boughs around and lightly over the plants. Boughs are great here. They shade the leaves and break the wind without matting down. Your Christmas tree can take over this job in January.
4. THINK ABOUT PLACEMENT
If a plant burns every single year, it might just be in the wrong spot. South- and west-facing beds that get winter sun and wind are the hardest. Most evergreen perennials are happier on the north or east side of the house, or under deciduous trees.
IF IT HAPPENS ANYWAY
Don't panic. Winter burn usually affects the leaves, not the crown. In spring, cut off the damaged leaves, and fresh growth will replace them within a few weeks.
Water now. Snow later.
CRISPY IS FOR CHIPS.