Most winter plant loss in Markham is not freezing. It is desiccation: evergreen foliage keeps losing water to dry winter wind and sun, while the roots sit in frozen ground and cannot replace it. The plant dies of thirst in the middle of winter.
That is why the shrubs worth protecting are mostly the ones that keep their leaves.
1. Cedar hedges, especially young or roadside ones
Emerald cedars are the most commonly damaged plant we see. Two separate problems: winter burn on the windward side, which turns foliage bronze or brown, and snow load splaying the whole hedge open.
For burn, a burlap screen on the windward and road-facing sides is enough; the hedge does not need to be mummified. For snow load, tie the hedge loosely with soft twine in a spiral from the base up, which lets it shed snow instead of catching it.
Cedars within a few metres of a road or driveway also take salt spray, which compounds the burn. A burlap screen handles both.
2. Boxwood
Same problem, lower to the ground, and often worse because boxwood sits where snow gets shovelled onto it. Burlap screening on exposed sides, and try not to bury it under the pile from the driveway.
If your boxwood browns every single winter in the same place, the cultivar is probably wrong for the exposure rather than the wrapping being inadequate.
3. Hydrangea, but only some kinds
This one depends entirely on the type, and it is worth knowing which you have.
- Big-leaf hydrangea, the blue or pink mophead, flowers on old wood. Those buds are formed by autumn and our winters kill them, which is why so many Markham hydrangeas are healthy, leafy and flowerless. These are worth protecting: a cage of chicken wire loosely filled with dry leaves around the base.
- Panicle and smooth hydrangea, the cone-shaped white ones, flower on new wood. They do not need protection at all. Leave them entirely alone.
4. Young Japanese maple
Hardy enough here once established, but the first three winters are the risk, and the danger is as much sun as cold. Winter sun on a thin young trunk warms the bark on the south-west side during the day; it refreezes at night and splits. That vertical crack is frost crack, and it does not heal.
Wrap the trunk with a light-coloured tree wrap or a loose burlap sleeve for the first few winters, and remove it every spring.
Wrapping the plant tightly in plastic, or in burlap pulled snug against the foliage. Plastic traps moisture and cooks the plant on the first sunny day. Burlap touching the foliage conducts cold straight to the leaf and freezes exactly what it is meant to protect. Build a screen with an air gap: stakes driven into the ground, burlap stapled to the stakes, foliage never touching the fabric.
Timing, and the step people skip
Wrap after the ground has frozen but before deep winter, generally the second half of November in Markham. Wrapping too early keeps plants warm through a mild spell and delays dormancy, which leaves them more vulnerable, not less.
The step that gets skipped: water everything deeply before the ground freezes. A late-autumn soak is the entire water supply an evergreen has to draw on until the thaw. Well-watered plants going into winter are dramatically more likely to come out of it intact, and it matters more than the burlap does.
Come off in spring, gradually
Remove wrapping in early April, ideally on an overcast day. Foliage that has spent four months shaded can scorch if it goes straight into strong spring sun.
We handle winter prep in the fall cleanup
Burlap wrapping, anti-desiccant and marker stakes go in during the last visit of the season, before the ground freezes.
