Fertilizing Green Giant Arborvitae in Pennsylvania

Feeding 85 Green Giants Planted Last Spring

A SW Pennsylvania homeowner planted 85 Green Giant arborvitae last spring. They're doing well and ask about spring fertilization (Miracle-Gro or other).

Fertilization Schedule

• Year 1 (establishment): No fertilizer. Focus on water and mulch.
• Years 2–4: ½ lb balanced fertilizer (10-10-10 or 20-20-20) per inch trunk diameter, spring and midsummer.
• Year 5+: 1 lb per inch trunk diameter, spring and midsummer.

Application Method

• Granular: Scatter under canopy, water in thoroughly.
• Water-soluble (Miracle-Gro): Mix per label, apply to soil—not foliage.

Critical Warning

Never use "weed and feed" or any herbicide-containing lawn fertilizer near these trees. Broadleaf herbicides (2,4-D, dicamba) will kill arborvitae.

Key Takeaway

Wait until year 2 to fertilize. Then use balanced granular fertilizer at ½–1 lb/inch trunk diameter, spring and midsummer. Keep all herbicide products far from the root zone.