Be honest about the odds first
Trees do not move the way palms do. A palm regenerates roots readily from the trunk base; a tree depends on a spreading permanent network of laterals and feeder roots, and lifting it severs most of them. What you leave behind is often eighty or ninety per cent of the root system, and the tree then has to support a full crown on what remains.
Transplanting works well for young trees, for species that root fibrously and shallowly, and where the move is planned months in advance. It fails routinely for mature trees, taprooted species and last-minute decisions.
If the tree is large and genuinely important, the alternative worth pricing is a professional tree spade or crane relocation — or accepting removal and planting a replacement, which is frequently the cheaper and better outcome.
Species and size
Good candidates on the Gold Coast: young lilly pilly, tuckeroo, frangipani, citrus, magnolia, bottlebrush, and most nursery-grown stock under about 75mm trunk diameter.
Poor candidates: eucalypts of any size with an established taproot, hoop pine, mature figs — whose root plates extend far beyond the drip line — and anything already showing dieback or decline.
Trunk diameter is the practical ceiling. Under 50mm is a hand job. Fifty to 100mm is hard work with two people. Over 100mm is machinery.
Timing in a subtropical climate
The southern-states advice of "move in winter dormancy" only half applies here, because most subtropical species barely go dormant.
The workable Gold Coast windows are late autumn through winter for deciduous and semi-deciduous species, when growth has slowed and the heat is off, and early spring for evergreens, so the tree has warm soil for root regeneration before summer.
Avoid moving anything from December to February. The combination of heat, high transpiration and storm wind on an unanchored tree is the most reliable way to kill it.
Root pruning in advance
This is the single highest-value thing you can do and almost nobody does it.
Six to twelve months before the move, mark your intended root ball radius and cut a vertical trench around the tree with a sharp spade, severing the roots at that line. Backfill the trench and water normally. The tree responds by producing a dense mat of fine fibrous roots inside the circle.
When you eventually lift, the ball contains a working root system rather than a few cut stubs. Survival rates go up markedly.
Lifting
Water deeply for several days first — a hydrated tree handles the shock better and the ball holds together.
Tie the lower branches up out of the way. Mark the ball radius and cut straight down all the way around with clean cuts, then undercut to free the base. Slide hessian or a tarp under and wrap the ball; the aim is to move it without the soil cracking off the roots.
Mark which side faced north, and replant it the same way. Bark on the previously shaded side is not adapted to full Queensland sun and will scald.
Move it immediately. A root ball drying on a lawn on a Gold Coast afternoon loses viability fast.
Planting
Dig the new hole twice as wide as the ball and no deeper. Plant at the same depth it was growing — the root flare should be visible at the surface. Planting deep is the most common killer.
Backfill with the excavated soil, not with a rich mix. In the clay through Nerang, Robina and Helensvale, a rich backfill in a clay hole makes a bathtub that drowns the roots. Firm in stages, water in to settle, and build a basin around the edge.
Stake only if genuinely needed for stability, low on the trunk, with flexible ties, and remove the stakes within twelve months. Ties left on girdle the trunk and create the failure point that shows up in a storm five years later.
Mulch to 75mm, kept well clear of the trunk.
Aftercare
Deep water two or three times a week through the first summer, more in a heatwave. No fertiliser for at least three months. Do not prune the crown back hard to "balance" the roots — the tree needs its leaves; remove only damaged material.
Expect a year or two of minimal growth. That is the tree rebuilding roots, and it is the normal pattern rather than a problem.
Related: moving a tree, transplanting palms, and removing a small tree and replanting. Ring (07) 5230 8034 or browse the blog.
Frequently asked questions
How big should the root ball be?
The working rule is roughly 25 to 30cm of root ball diameter for every 2.5cm of trunk diameter measured at chest height. A 10cm trunk therefore wants a root ball around a metre across. Depth is usually about two-thirds of the width, because most feeder roots are in the top 30 to 60cm of soil rather than deep down.
What is root pruning and do I need to do it?
Root pruning means cutting a circle around the tree at your intended root ball radius several months before the move, then leaving it in place. The tree responds by producing dense fibrous roots inside that circle, so when you finally lift it the ball contains far more working root. For anything valuable, do it six to twelve months ahead — it dramatically improves the odds.
Which trees will not survive a move?
Anything with a strong taproot — many eucalypts, oaks and hoop pine — because the taproot is severed and cannot be replaced. Anything over about 100mm trunk diameter without professional equipment. Anything already stressed, diseased or in decline. And anything moved in the wrong season. Be honest about these before investing effort.