Alberta winters aren't just cold — they're erratic. A January Chinook can swing temperatures 30°C in a day, thawing plants that then refreeze hard overnight. That freeze-thaw cycle, not the cold itself, kills more perennials than anything.
Mulch after the ground freezes
Wait until the soil is frozen, then pile 10–15 cm of straw, shredded leaves or bark over perennial crowns. The goal isn't to keep them warm — it's to keep them consistently cold and insulated from Chinook thaws.
Protect the vulnerable
- Broadleaf evergreens (cedar, boxwood): wrap in burlap to prevent winter desiccation from dry winds and sun.
- Roses & tender shrubs: mound soil or mulch over the graft; consider Zone-3-hardy varieties next time.
- Tender bulbs (dahlia, canna, gladiolus): dig before hard frost, dry, and store in a cool, dark, frost-free spot.
Snow is your friend
Snow is the best insulator there is. Shovel clean snow onto perennial beds and the base of shrubs, and avoid using salt where melt will run into planting areas. Hold off hard pruning until spring — dead top growth catches snow and shields the crown.
Check your first/last frost dates anytime by setting your city on the homepage.