The technical sequence for planting a mature tree

Planting a mature tree should follow a prepared sequence. The order reduces handling, allows the level to be corrected while the crane is still taking the weight, and avoids leaving the rootball exposed while it waits for the site.

The process begins before the lorry arrives. Position, access, soil, drainage and lifting equipment are confirmed against the actual specimen.

The design gives the location, but on the ground the team checks the distances to buildings, services, paving and other trees.

The specimen code, the species, the size and the orientation chosen at the nursery are confirmed.

When the crown has a more open or a denser side, the direction is marked before the lift.

A change of position should be approved before the planting hole is opened or the tree is lifted from the ground.

Opening up the profile shows texture, compaction, made ground, water and services.

How the soil behaves decides the volume to prepare and whether drainage is needed. The same planting hole does not suit every location.

The finished level of paving and mulch is also confirmed. The tree should sit correctly once all the finishes are in place.

As a minimum reference, Diaplant prepares the soil in width and depth to at least twice the dimensions of the rootball, adjusting to the ground and the species.

The deeper excavation serves to loosen and decompact the profile; it does not change the final level of the tree. The base is firmed so that the root collar stays at finished ground level, or slightly above where necessary.

In compacted soils, the larger the functional volume connected to the surrounding ground, the better establishment and growth tend to be. Drains and outlets, where needed, are built and tested before the tree arrives.

Stakes, guy wires or underground anchoring should be to hand before unloading.

If the system uses components beneath the rootball, the base is prepared to receive them.

The position of the stakes should not mean driving them through the rootball once the tree is planted.

On arrival, the checks cover identification, moisture, the integrity of the rootball, the trunk, the crown and the protection.

Any damage is photographed and reported before the tree is placed.

The unloading order is confirmed against the planting plan.

The lifting technique depends on the shape, weight and proportions of the specimen.

Younger, lighter trees can be moved by the trunk with specialist padded slings. Multi-stems and shrubs can take slings under the rootball, without compressing it, and a second support on a trunk or structural branch.

On very large trees, the main load is taken at the rootball. The support on the trunk steadies rotation and helps to hold the set angle. The first lift is short, to confirm the balance before moving the load to the planting hole.

The tree is set down on the base and turned to the chosen direction.

While the crane holds part of the weight, the team confirms that the tree is upright or at the intended lean, its height and how the crown relates to the space.

Small corrections at this stage are safer than trying to turn the rootball after backfilling.

The top of the rootball may carry accumulated soil. The team identifies where the structural roots begin at the trunk.

As a rule, the root collar sits at finished ground level, or slightly above when the soil and the species justify it.

The graft union is no substitute for this reference.

On rootballs prepared by Diaplant, the certified hessian and wire mesh stay in place during planting.

Removing or loosening them is not recommended, because the operation can compromise the cohesion of soil and root.

Only the external ties next to the trunk that might constrict tissue are checked, without dismantling the system.

The soil is placed evenly around the rootball. Large voids are filled without heavy compaction.

Its composition should make a transition to the existing ground. A very different mix can keep the roots confined.

The level is rechecked as the soil settles.

The tree is watered in deeply, by flooding. The water settles the soil, reduces air pockets and improves contact with the rootball.

As a general rule, a slow-release NPK fertiliser is also applied, at a rate adjusted to the specimen and the soil conditions. The product is spread out, with no direct concentration next to the roots.

After watering, the level, the drainage and the stability are confirmed.

The system is installed to suit the size, the crown and the exposure.

The ties are protected, visible and accessible for inspection. The tree should not be held completely rigid, but the rootball must not be able to rotate.

Guy wires at ground level are marked when they pose a hazard.

The surface is shaped to take water without it collecting against the trunk.

An organic mulch or other finish is applied, keeping the base of the tree clear.

Temporary crown protection is removed with care, watching for branches under tension.

The date, team, tree, orientation, volume of the first watering, staking and soil conditions are noted.

Photographs of the level, the root collar and the systems are linked to the position.

The maintenance plan states who checks moisture and stability.

Over the following days, settlement, moisture and the tension of the ties are checked.

After rain or strong wind, the inspection is repeated.

Planting ends when the tree is in place and recorded. Adaptation begins at that moment and calls for continuity.

• Planting mature trees
• The root collar and planting depth
• How to monitor adaptation

1. European Arboricultural Standards. European Tree Planting Standard.
2. Diaplant’s planting and site control method.