How to Transplant a Holly Bush
Transplant holly in late fall or early spring while it is dormant. Root-prune a large plant a season ahead if you can, dig a wide root ball, keep it intact, replant at the same depth in acidic soil, water deeply, and mulch. Expect some transient leaf or berry drop.
Holly moves best when it is dormant, in late fall or early spring, so the roots can re-establish before the stress of summer heat. Moving a holly in active growth or in the heat of summer sharply raises the risk of failure.
For a large, established holly, root-prune it a season in advance if you can: slice a circle through the roots around the planned root ball several months before the move so the plant grows a compact mass of feeder roots to take with it. When you lift the plant, dig a root ball as wide and deep as you can manage and keep the soil intact around the roots.
Replant immediately at the same depth it grew before, in a wide hole in moist, acidic, well-drained soil. Firm the soil, water deeply to settle it, and spread mulch over the root zone. Keep the plant well watered through its first year, and do not be alarmed by some leaf yellowing or berry drop afterward — that transplant shock is normal and eases as the roots take hold.