Planting Thuja: Skip Fertilizer, Mulch Correctly

A homeowner planting 3-foot Thuja trees asks about using 13-7-7 fertilizer and whether to mix composted mulch into backfill or apply on top.

First Year: No Fertilizer

Fertilizer burns tender new roots. Wait one year before feeding.

Mulching Technique

• Apply mulch in a donut shape around the tree—keep it off the trunk.
• Depth: no more than 3 inches.
• Purpose: moisture retention, temperature moderation.

Backfill with native soil; amendments can create a "bathtub effect" hindering root expansion.