Why Topping White Spruces Is Destructive—and Better Alternatives

Topping (heading back the central leader) will kill or permanently deform your 20-ft white spruces. Conifers rely on a single dominant terminal bud for apical dominance and natural form. Removing it triggers chaotic, weak, multi-stemmed regrowth—or death if the tree cannot compensate.

Side Pruning: Acceptable If Done Correctly

• Timing: Late winter/early spring (dormant) to minimize sap flow.
• Method: Cut back to a living lateral branch with green needles—never leave a bare stub. A stub will die back to the trunk.
• Extent: Remove no more than 1/3 of live crown in one season.
• Result: The sheared side will remain bare at the trunk; the tree will develop a lopsided, open-grown appearance.

Hedge Formation

Your offset, staggered planting (7 ft apart, two rows) will eventually create a continuous screen as crowns merge. This is a legitimate design strategy—but do not top to force density. Instead, shear the outer faces lightly each year after new growth hardens (late June/July) to encourage branching within the canopy.

Bottom Line

Preserve the central leader. Shape the sides judiciously. Accept the natural pyramidal form—it’s the tree’s strongest, healthiest architecture.