Techny Arborvitae Mature Width: Plan Your Spacing

8 Techny arborvitae, 6 ft tall, 6 ft apart in partial shade. How wide at maturity? Internet says 4–15 ft.

Mature Size: 10–15 ft Wide, 15+ ft Tall

'Techny' (Thuja occidentalis 'Techny') reaches 12–15 ft wide at maturity (10+ years). At 6-ft spacing, they'll merge into a solid hedge.

Maintenance Reality

• Annual shearing (spring + fall) needed to keep narrow.
• Height control: Top at desired height yearly.
• Shade tolerance: Partial shade OK; full sun = denser.

If you want a low-maintenance screen, consider narrower cultivars ('Emerald Green' 3–4 ft wide) or wider spacing.