Frequently asked questions

It means selecting for the space the tree will occupy in future, above and below ground. Street width, façades, sight lines, services, soil, water and maintenance should be looked at together. A tree that has to be cut back every year is the wrong size for its place. The specification should state species, cultivar, form, clear stem height and planting conditions, not just the name.

There is no universal volume. What is needed depends on the tree’s eventual size, the species, the climate, the water and the quality and continuity of the soil. A compacted or waterlogged volume is not equivalent to the same volume of porous, free-draining soil. Guide figures should state their assumptions and be backed by monitoring of the trees’ growth and condition.

Mainly through shade and evapotranspiration. Shade reduces the radiation reaching people and paving; evapotranspiration uses water and energy. The effect depends on the position of the crown, the urban form, the species and the availability of water. Young planting takes years to give the cover of a mature tree, so keeping existing canopy is essential.

Diversity reduces reliance on a single species, genus, family or age in the face of pests, diseases and climatic extremes. It should be planned by street and by landscape unit, keeping form, rhythm and scale. A long list does not make up for too little soil or poor maintenance. The strategy needs an inventory and monitoring to learn which species work in each set of conditions.

It is a guideline that proposes seeing three trees from home, school or work, living in a neighbourhood with 30% canopy cover and having a public green space within 300 metres. It is useful for diagnosis and communication, but it does not assess health, diversity, soil, water or the quality of the park. It should be applied methodically and not treated as an automatic seal of approval.

Planning, setting out, protection of existing features, earthworks, services, structures, paving, soil preparation, planting, testing, handover and initial maintenance. Some areas can move forward in parallel, but dependencies must be respected. Services are tested before they are covered, large trees go in before access is blocked and the planting soil is protected once it has been prepared.

No. Shrubs and perennials normally go in after the heavy work, but large trees may need to be planted before paving, walls or railings are finished. Access for the crane and the lorry dictates the sequence. The tree is protected while the rest of the work goes on, and the soil must not be used as a site compound again.

Because they all share the ground with roots, foundations and paving sub-bases. Without coordination, you end up with chambers next to trunks, cables under planting holes or pipes that cut off root continuity. The designs should be drawn on the same base plan, show depths and allow for maintenance. Buried services are tested and photographed before they are covered.

First you identify where the water comes from, the route it takes and where it ends up. The solution may combine ground modelling, infiltration, ditches, gullies, chambers and land drains. A permeable surface only works if the layers beneath it also have capacity. Construction includes levels, testing and access for cleaning. When a puddle appears, look for the cause before adding another gully.

Ground modelling sets levels, paths, terraces, banks, walls and the movement of water. Changing the landform after the services and paving are in means redoing work. Cut and fill also change the quality of the soil and the relationship with existing trees. Planting softens the ground, but it does not put right an unsafe slope or drainage with no outlet.

A conventional swimming pool uses mechanical and chemical treatment, or equivalent technologies, for bathing. A natural pool includes filtration and, in several systems, planted zones, but it still needs equipment and maintenance. A pond may be designed mainly for contemplation, plants or wildlife, and has different parameters. The brief, the water quality and the capacity for maintenance should be defined before the shape.

Once the soil has been prepared and the irrigation and drainage tested, the trees go in first, followed by large shrubs, massed shrubs, perennials, ground-cover plants and mulches. The setting out is confirmed before all the holes are dug. Each area is watered straight after planting. Mulch or aggregates are only applied once species, spacing, level and finish have been checked.

The aims of the garden, an inventory, tasks, frequencies, criteria, responsibilities and records. Trees, shrubs, perennials, lawn, irrigation, lighting, drainage and water features each need their own treatment. The plan should distinguish between establishment and the mature phase, and explain what look is to be maintained. It is not just a schedule of cutting and tidying.

No. The months work as windows. Altitude, aspect, proximity to the sea and the year’s weather shift bud break, flowering and drought. The condition of the plant takes priority over the date. The calendar organises watering, planting, pruning, weeding and testing, but it should be updated with observations from the garden itself.

Yes, provided they are treated as working areas. They need soil, sun, water, access, harvesting, pruning and management. A kitchen garden in daily use, a domestic orchard and a productive vineyard differ in scale and in the knowledge they call for. The design can weave production into the landscape, but it should not promise yield or self-sufficiency without an agronomic study and a real capacity for maintenance.

Diaplant brings together a nursery of mature ornamental trees, landscape architecture and the construction of outdoor spaces. The company follows the whole journey, from growing and selecting the specimens to design, transport, planting, construction and aftercare. This integration lets information about the tree and about the place pass between teams, rather than each stage starting with no knowledge of the one before.

Diaplant is based in Amarante, in northern Portugal. Production is spread over three sites and covers around 33 hectares. Visits to the nursery should be arranged in advance, especially when the aim is to select mature trees or compare several specimens for a project.

Diaplant started trading in 2009. The company grew out of the production of ornamental plants and trees and gradually extended its work to the design, construction and follow-up of outdoor spaces.

Diaplant’s production area is around 33 hectares, spread over three sites. Most of the trees are grown in the open field, because this system makes it possible to develop specimens of mature size and to work the roots through successive transplantings. Container growing exists, but it accounts for a very small share or serves as a transitional stage for certain specimens.

Diaplant grows more than 150 species and cultivars itself and sells more than 600 lines when specialist partners are included. These figures describe the breadth of the range, not permanent availability. What is actually on offer varies with production cycles, the season, the batches and the reservations already in place.

No. Its own production is central, especially for mature trees and larger specimens, but the range on sale is complemented by partners. This distinction should be transparent: origin, production system, form and quality are confirmed for every consignment. Working with partners means a project can be completed without presenting as home-grown anything that was not grown in Diaplant’s fields.

No. The company has experience of supplying several European markets and a commercial presence in nine countries. Whether each operation is feasible depends on the species, the size, the season, the plant health documentation, the transport and the planting conditions at the destination. With mature trees, distance makes logistical planning and continuity of information all the more important.

Diaplant develops landscape architecture projects, supplies and transports trees, carries out planting and builds outdoor spaces. The works may include ground modelling, walls, paving, irrigation, lighting, water features, the complete installation of the planting, and maintenance. The scope is defined for each project; there is no obligation to contract all the areas together.

The Diaplant method describes the continuity between nursery, design, transport, planting, construction and follow-up. The team aims to keep the information about the specimen and about the place throughout those stages. It is not a promise that every condition will be under control, nor does it oblige you to contract everything; it is a way of reducing losses of information and taking decisions further ahead.

Yes. A client can buy plants, ask for selection at the nursery, or contract design, planting, construction or a combination of these areas. The scope should make clear the responsibilities, the information to be handed over and the follow-up included. Where different teams are involved, Diaplant recommends that details of rootball, orientation, watering, access and maintenance are passed on to avoid contradictory decisions.

A species is a botanical unit, such as *Acer palmatum*. A cultivar is a selection maintained in cultivation for specific characteristics, such as ‘Bloodgood’ or ‘Garnet’. Cultivars of the same species can differ greatly in size, leaf, colour and habit. When the design depends on those characteristics, the full name should appear in the specification.

A tree generally has a clearly defined main trunk and a crown held clear of the base. In a multi-stem, several trunks or main stems rise from the ground or from very low down, while it still reads as a tree and keeps a clearly recognisable vertical structure. In a shrub, or a shrub form, branching starts close to the base, with more branches and a denser mass, and no clear separation between trunk and crown. In some cases the same species can be grown in more than one of these forms.

These terms indicate the height at which the crown begins. A standard tree has a clear stem up to a relatively high point; a half-standard branches lower down; a low standard brings the crown close to the ground. The limits vary between nurseries, so the clear stem height should be stated when it matters for circulation, privacy or the relationship with buildings.

A natural crown follows the natural architecture of the species. A globe crown forms a rounded volume, through habit, grafting or pruning. A columnar crown grows mainly upwards, but still gains width. A pleached crown is trained on a frame, as an espalier or a roof-trained crown, and needs regular maintenance. The form should be chosen with the mature size and the future work in mind.

A grafted tree combines a rootstock, which provides the roots and part of the trunk, with a cultivar that forms the crown or the ornamental part. The technique preserves characteristics that do not come true from seed and can fix the height of the crown. The union should be sound and any shoots below it should be kept in check.

No. Planting depth should be set by the root collar, not by the graft union. Burying the union or the trunk to hide a difference in diameter can keep tissue in contact with damp soil and encourage problems. With low grafts, the transition between trunk and roots needs to be located carefully before the hole is backfilled.

No. A columnar form reduces crown spread, but the tree still grows, gains height and needs soil volume. Façades, cables, lighting and branching height also need to be assessed. A narrow cultivar solves only part of the conflict above ground; it does not make up for a small tree pit or underground services with no room to spare.

First you define what the planting needs to do: give shade, screen views, structure the space, flower, support biodiversity or reduce maintenance. Then you translate that function into criteria such as spread, clear stem height, whether the foliage is evergreen or deciduous, flowering season and water use. A single plant rarely maximises every function; combining layers usually gives a more consistent answer.

The choice weighs up available space, sun, heat, wind, soil, drainage and water. A species suited to the regional climate can fail in a hot courtyard, on a sandy bank or in a waterlogged spot. The design should first assess the conditions that will remain after the works, and only then compare species, cultivars, forms and sizes.

No. The shade varies with the cultivar, the season, the light, the heat and the water. In deep shade, some leaves turn greener; with heat and dry roots, they can scorch and lose quality. Upright cultivars and Dissectum forms also differ in habit and sensitivity. The choice should start from the full name and the site, not just from a photograph.

As a rule, during dormancy. At Diaplant, the main season runs from November to April. The actual window depends on the species, the state of the foliage, the weather and the soil at the nursery and on site. A date within that period does not justify lifting when the ground is waterlogged, the rootball will not hold together or the tree has already started into growth.

Not exactly. Evergreens keep their leaves and go on transpiring, even at low temperatures. They benefit from the cool season, but need closer attention to rootball moisture, protection in transit and wind. The timing should also take into account how sensitive the species is to cold around recently disturbed roots.

The team confirms the specimen and the destination, assesses the condition of the tree, sets the rootball size, forms and wraps the root mass, protects the crown and trunk and works out the weight and the lifting equipment. The load is arranged in unloading order. The aim is to preserve the structure the tree had in the field and to shorten the time between lifting and planting.

The method depends on the form, the size, the weight and the proportion between crown and rootball. Younger, lighter trees can be lifted by the trunk with specialist padded slings, positioned to balance the centre of gravity. With multi-stems and shrubs, the slings go round the rootball without compressing it or damaging the root structure. A second support may be needed, with a padded sling on a trunk or structural branch, to steady the specimen at an angle of around 45°. With very large trees, the main lifting point should stay on the rootball, using suitable anchoring equipment, with the support on the trunk used only to balance the tree and control its position. Unusual forms may call for specialist techniques and equipment.

The crown is tied in gradually with materials that spread the pressure and prevent rubbing. The trunk can be protected with reused coffee sacks, cotton mesh, coir or purpose-made materials, depending on the specimen. The protection should breathe, not constrict and allow inspection. The aim is to avoid abrasion, breakage and excessive drying out.

Not as a rule. First the tying-in, the vehicle, the route and the equipment are adjusted. Pruning is only justified where there is a damaged branch, a structural problem or a specific incompatibility that cannot be resolved any other way. Reducing the crown simply to make the logistics easier removes foliage, reserves and a form built up over years.

A crane’s capacity falls as its reach increases. A machine that can lift the weight close to its base may not be able to place it several metres further out or over a wall. It also needs space and firm ground for its outriggers. Rootball weight, distance, wind, the overhead path and the position of the planting hole should all be confirmed before dispatch.

Gates, bends, headroom, gradient, the load-bearing capacity of the paving, the area for the outriggers and the distance between the crane and the planting hole should all be measured. Cables, eaves, walls, trees and other structures come into the overhead path. Photographs and a plan help, but a technical visit is advisable where the size or the difficulty is considerable.

Not always. On many projects, the paving, walls or railings close off the access the lorry and the crane need. Large trees may have to go in before those finishes are completed, and are then protected while the rest of the work goes on. The sequence should be planned from the design stage to avoid demolition and soil compaction.

It may be necessary to choose a smaller size, a more compact crown or a different production system, or to bring planting forward to a stage when access is open. A crane with a longer reach may also solve it, but it needs more space and capacity. The decision should be made before lifting; adapting the tree at the moment of delivery creates technical and logistical risk.

A mature tree is a specimen that has spent several years in production and has a trunk, crown and root system ready to give the project an immediate presence. There is no single age or measurement that applies to every species. The concept takes in production maturity, transplantings, crown formation, the ability to form a functional rootball and enough quality to leave the field.

‘Large’ mainly describes the visible size. ‘Mature’ adds the history of production and preparation. A tree can be tall and yet have roots that have had little preparation, an unbalanced crown or only a short time in a container. The assessment should bring together girth, height, form, roots, transplantings and the condition of the specimen. Size matters, but it is no substitute for quality of production.

At Diaplant, every tree in the mature range spends at least six years in the company’s fields and is transplanted at least twice. In the most mature batches, production can run to 15 to 20 years and include up to five transplantings. The time and the number of cycles depend on the needs of each species, the size wanted and how the tree recovers between operations.

A tree can be transplanted several times during production. At Diaplant, two transplantings are the minimum, but the most mature batches can generally reach five, often corresponding to 15 to 20 years of production. The number and the interval vary with the needs of each species. The aim is to keep a functional quantity of roots close to the future rootball, always giving the tree time to recover before the next cycle.

Transplanting cuts some of the long roots and stimulates roots to form closer to the trunk. Over time, the tree develops a more concentrated root system that can travel with the rootball when it leaves the field. The operation also makes it possible to reposition, select and shape the specimen. It is not something repeated by the calendar; it depends on the species, the soil, the vigour and the recovery.

The cut roots lose part of their capacity to absorb and begin a period of recovery. New fine roots form near the cuts and occupy the available soil. The crown may slow its growth for a time while the tree rebalances root and leaf. Water, oxygen, temperature and freedom from further disturbance are decisive during this phase.

The rootball is the volume of soil and roots that goes with a field-grown tree. Its job is to keep an active part of the root system intact during lifting, transport and planting. A bigger rootball is not automatically better: it needs to contain roots, hold together and be compatible with the species, the size, the weight and the logistics.

It depends on the species, the size, the season and the project. Field growing makes it possible to form large mature trees and to prepare the root system through successive transplantings. A container gives more flexibility over timing, but it should be assessed for how long the tree has been in it, the stability of the rootball and possible root deformation. The production system is no substitute for assessing the individual specimen.

The assessment covers roots, rootball, root collar, trunk, crown, form, vigour and production history. Girth and height are not enough. What is wanted is a structure consistent with the species and the function, free from serious damage, problematic unions or imbalances that would call for heavy corrective work. Quality also depends on the tree being ready to leave at that moment.

The team weighs up the time since the last transplanting, the condition of the crown, the vigour, the ability to form a rootball that holds together and the dispatch season. Excessive growth may indicate that the tree is too well established and needs preparing again; too little vigour may point to incomplete recovery. The decision should not be taken simply because there is an order.

The position, the soil, the drainage and the equipment are prepared before the tree arrives. The tree is lifted by the rootball, oriented, set with the root collar at the correct level, backfilled without heavy compaction, watered deeply and stabilised. The sequence is recorded so that moisture, staking and the crown’s response can be monitored over the following months.

As a minimum guide, Diaplant recommends preparing the soil to a width and depth of at least twice the dimensions of the rootball. Each case should be assessed according to the soil on site, the drainage, the size and the specific needs of the species. The greater the volume of soil that is loosened and decompacted around the tree, while keeping a stable base and without creating drainage problems, the better the conditions for the roots to spread and for the tree to adapt and go on growing in its new position.

No. The deeper excavation is there to loosen and decompact the soil below and around the rootball; the tree is still set with its root collar at finished ground level, or slightly above where the soil and the species justify it. The guide of twice the depth is a minimum for preparation and should be adapted to each case. The more functional, decompacted soil there is available, the better establishment and growth tend to be, provided the base stays stable and the water can drain away.

For a large tree of medium maturity, a volume of 2 × 2 × 2 metres can be an ideal guide for prepared soil where the site allows. It is not a universal requirement, nor does it apply without knowing the rootball and the ground. In well-structured agricultural soil less work may be needed; on a compacted platform, a different approach may be called for.

The root collar is the zone where the trunk passes into the structural roots. It should stay at the surface. The top of the rootball may have soil built up on it and not show the true level, so the base of the trunk should be checked before backfilling. Planting too deep reduces oxygen, keeps the bark damp and can cause problems that only show up later.

On rootballs prepared by Diaplant, we do not recommend removing or loosening the mesh and hessian. The materials are applied to hold soil and roots together during transport and planting. Opening up the system can cause cracks, lose soil and compromise viability. This guidance applies to the method and materials used by Diaplant; for trees from other sources, the grower’s advice should be confirmed.

Because opening it can release the compaction achieved at the nursery and start cracks that run through the rootball. On heavy specimens, the loss of cohesion can leave roots exposed, and rebuilding the mass is not straightforward. On rootballs prepared by Diaplant, the mesh and hessian are part of the system that protects the root structure and should stay intact. At the root collar, simply check whether any tie is pressing directly on the trunk, without dismantling or loosening the rootball.

It depends on the girth, the crown, the wind, the species and whether the tree is deciduous or evergreen. In Diaplant’s practice, two stakes are usual up to a girth of 20–25 cm; three may be used on larger sizes; big specimens may need angled guy wires. These ranges are a guide. The aim is to stabilise the rootball without holding the crown completely rigid.

Underground anchoring is useful when an immediate finish with no visible stakes is wanted, when circulation does not allow above-ground supports, or for trees and multi-stems whose form would be spoiled. The system needs a suitable base and an installation compatible with the rootball. It can work on its own or reinforce other staking, depending on exposure and size.

The first watering wets the rootball, settles the soil, reduces air pockets and improves contact between roots and ground. It also lets you observe infiltration, run-off and any drainage failures. Even with automatic irrigation, a watering by hand may be needed to make sure the water reaches the whole root mass and the surrounding soil.

The landscape architect works on the relationship between ground, planting, water, materials, buildings and use. They analyse the place, organise the spaces, set levels, select plants, coordinate infrastructure and prepare the information needed to build. The work is not just a matter of choosing species or producing images; it includes decisions on drainage, access, maintenance and future development.

The process may include first contact, briefing, survey, analysis of constraints, concept, concept design, applicable procedures, detailed design, preparation for construction and technical assistance. The depth varies with the scale. Stages can be adjusted, but they should not disappear without it being clear which decisions are left unresolved or who will take them.

The briefing is the first structured conversation before design begins, and its purpose is to understand how the client wants to live in and use the space. It should cover who uses the garden, routines, the functions wanted, the relationship with the house, privacy, views, planting, water, animals, accessibility, level of maintenance, timescale, priorities and the budget range. Plans, a topographical survey, photographs and information about services help to reduce guesswork. More than a wish list, the briefing should distinguish between what is essential, what is desirable and what still needs to be decided.

The concept design defines the layout, uses, main levels, ground modelling, materials, structural planting and the relationship with water and lighting. It may include an illustrated plan, sections, moodboards, 3D views and an initial estimate. It does not yet contain all the details needed to build. It is there to compare alternatives and agree the direction before investing in the detailed design.

It includes the documents needed to measure, coordinate and build: general layout plan, ground modelling, drainage, paving, structures, irrigation, lighting, planting plan, details, specifications and quantities, depending on the scope. The design should be coordinated with the other disciplines and identify its revisions. An approved image is no substitute for levels, thicknesses, services or quality criteria.

No. A render conveys atmosphere, materials and scale, but it does not resolve drainage, structure, waterproofing, irrigation or licensing. It may also show mature plants or materials differently from what will actually be supplied. Construction needs plans, sections, details, specifications and quantities that match the approved image.

Because it affects area, materials, walls, infrastructure, water, tree sizes and phasing. Putting the conversation off can mean reworking a solution that has already been developed. Where there is no clear figure, scenarios and priorities can be compared. The aim is not to limit creativity, but to focus resources on the decisions with the greatest impact and avoid a proposal that cannot be built.

It depends on the work and on the plot. Walls, swimming pools, structures, access, services, ground modelling and soil sealing may be subject to procedures or constraints. The PDM (municipal master plan), the easements and the legislation in force need to be consulted, and each element assessed. A garden should not be declared automatically exempt simply because of its size or because it is outdoors.

By choosing compatible plants, allowing for mature size, setting the right planting densities, covering the soil, separating irrigation zones and ensuring access to equipment. Trained forms, intensively managed lawns and water features can be appropriate, but they bring a known amount of work. ‘Low maintenance’ comes from the fit between place, design and resources, not from a universal list.

When there are many trees, public space, conflicts with infrastructure, an ageing tree population or goals for shade and climate adaptation. The project takes an inventory, sets priorities, reserves soil, selects species and plans planting and management. On private properties there may be a simplified version to guide structural trees and phasing.

Yes. Selecting in person lets you compare crown, trunk, orientation, scale and character. It is especially useful for mature specimens, multi-stems, macro-bonsai and trees that will occupy a focal position. The visit should be booked and backed by information about the project, so that the choice does not simply fall on the most eye-catching specimen.

A simple plan, measurements of the space, photographs, orientation and the intended function make the visit far more useful. Access to the site should also be known: gates, bends, paved surfaces and the distance to the planting hole. This information makes it possible to relate the form of the tree to the place and avoids selecting a specimen that cannot then be transported or planted.

Girth is the circumference of the trunk measured at a reference height. ‘Girth size’ can mean circumference or diameter, depending on the market, and should state the method and the unit. Height is measured from the base to the highest point. Pot volume indicates the approximate capacity of growing medium, but does not in itself reveal the age, the root quality or the maturity of the plant. These measurements should be read alongside the form, the crown and the root system.

No. Two trees with the same girth can differ greatly in clear stem height, spread, volume and structure. Girth helps to grade the trunk, but it does not describe the quality of the roots, the shape of the crown or the maturity of the specimen. In avenue planting, clear stem height may be more critical; for a free-standing specimen, orientation and volume may count for more.

Uniform batches matter in avenue planting, entrances, car parks and formal compositions, where the trees are compared side by side. Selection looks for a match in girth, clear stem height, volume, form and vigour. Absolute sameness is not required, because trees remain different organisms. The design should state the essential attributes and the tolerances.

Not in the absolute sense. Even within the same batch, each tree responds differently to soil, light and production operations. Matching specimens can be selected to create rhythm and continuity, but small differences remain and may grow or shrink after planting. Uniformity should be defined by useful criteria, not by an expectation of exact copies.

The larger the size, the quantity or the degree of uniformity required, the earlier selection should begin. Reserving early makes it possible to confirm availability, follow batches, prepare the logistics and, in some cases, carry out production operations before the trees leave. The reservation should set out the specimen, the timescale, the terms and the period of validity, because the tree is still alive and still changing.

No. Availability depends on production cycles, the season, the state of the batches and the reservations already in place. A catalogue describes the range and the forms grown, but it should not be read as permanent availability. Confirmation is given for the specific date, quantity and project.

No. Plants of standard specification can be selected by the team against agreed criteria, with a photographic record. A visit becomes more valuable when individual form, orientation, size or uniformity affect the project. With large specimens, it also helps in preparing transport and relating the rootball and crown to the access on site.

Photographs help with comparing and approving, but they do not show the full scale, depth and asymmetry. One side of the crown may be more open, the trunk may have a particular orientation and the spread can be hard to judge. For important decisions, the images should include several angles, measurements and context; a visit is still the most complete way to assess a tree.

There is no fixed frequency. It depends on the species, the rootball, the soil, the drainage, the exposure and the climate. The aim is to water deeply and let the soil regain oxygen before the next watering. In sand, the interval tends to be shorter; in clay, it may be longer. The decision should be based on the moisture found at the roots.

The volume depends on the size of the rootball and the capacity of the soil. A universal figure would be unreliable. You need to know the flow rate of the emitters, apply enough water to pass right through the root mass and confirm the depth wetted. Minutes of irrigation with no information on output do not allow litres to be calculated or systems to be compared.

Not necessarily. A short watering may dampen only the top few centimetres, while the inside stays dry. The reverse also happens: a dry surface can hide water lying at depth. Differences in texture between the rootball and the soil change how water moves. The check should be made at the roots and in more than one place.

Diaplant recommends small inspection holes beside the rootball, around 20 cm deep, made without damaging roots. The soil taken out shows whether it is dry, moist, sticky or has an anaerobic smell. The check should be made on more than one side, because an emitter or a slope may wet only part of the tree.

No. Wilting can result from a dry rootball or from waterlogged roots starved of oxygen. In both cases, the crown stops receiving enough water. Before increasing the watering, check the soil, the drainage and the distribution. Watering a waterlogged tree makes the suffocation worse; leaving a dry tree waiting for a diagnosis is also risky.

Waterlogging occurs when the soil pores stay filled with water and the roots are short of oxygen. The fine roots slow down or die, and the crown may wilt even though water is present. Compaction, isolated planting holes, leaks and low-lying ground are common causes. Putting it right starts with reducing the water coming in and identifying a way out for it.

Soil profiles are dug, the layers and any signs of waterlogging are noted, and an infiltration test can be carried out by filling a hole and watching how fast the water drops. The result should be compared between points and read in the light of the starting moisture and the time of year. Levels, springs, discharge points and where the water could go are also checked.

Not on its own. Crushed stone creates pores, but not an outlet. Water may sit in the layer or build up above the interface between materials. A drainage system needs a fall, pipework or a route, and somewhere workable for the water to go. Crushed stone can be part of a designed solution, but it should not be used as an automatic answer to a heavy soil.

First the depth and extent of the compaction are identified. The preparation should connect the planting zone sideways to the surrounding soil, break up any smeared sides and be done only when the clay is not waterlogged. Organic matter can gradually improve the structure, but it does not make up for a dense layer at depth. Drainage also needs to be confirmed.

The preparation aims to increase water retention and organic matter over a wide area, without creating a small pocket very different from the surrounding ground. Mature compost and organic mulch help progressively. Irrigation may need several points and cycles so that water is not lost below the roots. Selection should favour plants compatible with the conditions that will continue to exist.

A full laboratory study is not always necessary, but a physical assessment is essential. Site history, profiles, texture, compaction and infiltration guide the design. Chemical analysis becomes useful when there are doubts about pH, organic matter, salinity or nutrients, or when the choice of species and crops depends on those values.

Generally, yes. At planting, Diaplant applies a slow-release NPK fertiliser, at a rate adjusted to the specimen and the soil conditions, to help the tree adapt and ensure nutrients are available through the first growing season. Fertilising complements soil preparation, watering and drainage; it does not put right a dry rootball, a waterlogged soil or planting that is too deep.

It depends on the garden. Woodchip and bark reduce evaporation, moderate temperature and add organic matter, but they need topping up. Gravel and other aggregates create a mineral look and last longer, but they can heat up and do not feed the soil. Leaf fall, slopes, maintenance, irrigation and the sensitivity of the plants should guide the choice.

Shorter growth, slightly smaller leaves or some partial leaf drop can occur during establishment. How marked they are depends on the species, the season and the size. Persistent wilting, progressive dieback of branches, instability, wounds at the base or a complete absence of bud break at the right time of year call for assessment. Adaptation should not be used as a reason to ignore a water or soil problem.

When there is rapid decline, an unstable tree, a trunk wound, a suspected root problem or a risk to people and property. Photographs help to pick out patterns, but they do not measure moisture, soil resistance or the condition of the rootball. The images should show the whole plant, a close-up, the base, the soil and the irrigation; if that information is not enough to identify the cause, an inspection in person is needed.