Pruning Arborvitae: Timing and Technique for Healthy Growth

When and How to Prune Arborvitae

Most arborvitae (Thuja spp.) require little pruning beyond height control. They do not regenerate from old wood, so aggressive cutting causes permanent bare zones.

Best Timing

• Late winter/early spring (dormant season) before new growth.
• Late spring after flush hardens (light shaping only).
• Avoid fall pruning—stimulates tender growth vulnerable to winter kill.

Pruning Guidelines

• Remove only the current year's growth (green foliage).
• Never cut into brown, woody stems—they won't resprout.
• For height reduction, cut leader just above a lateral branch.
• Shear sides lightly for density; keep base wider than top for light penetration.

Resources

• GardenersNet Arborvitae Care
• AboutArborvitae Pruning Guide
• UBC Botanical Garden Forum

Less is more: a light annual trim maintains form without compromising health.