Arborvitae Growth Near a Cedar Fence: Spacing, Moisture Risk, and Timeline

Arborvitae planted 10 inches from a cedar fence will eventually touch it. Most varieties grow 6-12 inches per year in width. At that rate, contact occurs in 1-3 years.

Growth Expectations

• Emerald Green: 3-4 ft wide at maturity, slow (4-6"/yr).
• Green Giant: 12-15 ft wide, fast (12-24"/yr).
• Techny/Nigra: 4-6 ft wide, moderate.

Moisture and Fence Damage

Constant contact traps moisture, accelerates rot, and promotes fungal growth on the fence. Cedar resists decay but isn't immune. Airflow is critical.

Solutions

1. Relocate trees: Best done now while small (fall or early spring). Move to 3-4 ft from fence.
2. Install a vapor barrier: Heavy plastic or metal flashing on fence face where contact will occur.
3. Prune aggressively: Shear the fence-side face annually. But this creates a bare zone and stresses plants.
4. Remove fence sections: Replace with wire mesh or open design where trees grow.

Neighbor Communication

Discuss shared concerns. A joint solution (relocating trees, modifying fence) preserves both the screen and the fence.

Act now—moving 3-ft trees is easy; moving 10-ft trees is expensive and risky.