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Talk to some people about gardening with disabled people and their eyes will suddenly light up - 'aha, they do it in raised beds, don't they?' You can almost see the vision in their mind's eye of a sterile concrete box structure planted with a few lonely African marigolds for two months of the year. Well, it doesn't have to be like that...

First of all, let's dispel two popular misconceptions:

MISCONCEPTION A

'Gardening by older or disabled people necessarily implies the use of raised beds.'

Certainly, you might find gardening much more comfortable if the soil surface is raised in some way, whether by a few centimetres or three quarters of a metre.

This is particularly true if you experience difficulty in bending or balancing or have restricted mobility generally. Raising the soil surface can make all the difference between being able to garden at all and finding it out of the question. However, people's needs and abilities vary. You might prefer to garden at ground level using lightweight, long-handled tools. Working at a straight-sided raised bed may be difficult if you use a wheelchair and cannot lean forwards to reach the soil or cannot twist your spine to work sideways on.

So the key message here is to find out what the most comfortable gardening position is and to provide plants at the appropriate height, whether this means raising the soil level or not. To add interest to the garden - and to cater for two or more people with different needs - it makes good sense to provide a range of growing surfaces at different heights, including some at ground level.

MISCONCEPTION B

'Raised beds are unusual and often not very attractive garden features which have not been around for very long and which require special expertise to install and manage for their use by disabled people.'

This is not true! The growing of plants at different levels is by no means new or unusual. A border on top of a retaining wall or along a flight of shallow steps, or even in a window box, is as much a raised bed as is a temporary tub, a purpose-built planter or a growing bag on a couple of breeze-blocks.

Raised beds should rather be seen as normal features of the design of any well-planned garden, equally relevant for disabled people and non-disabled people alike and with great potential for enhancing the attractiveness of a garden.

What do raised beds have to offer?

For many (but not all) they considerably increase the opportunities for gardening by bringing both soil and plants within easy reach.
If you only have a tiny balconies or backyard, you may find that growing plants in raised beds or containers is the only way you can do gardening at all.
They can be useful ways of dividing a garden into distinctive areas, or of providing privacy.
In some gardens, the slope, soil depth, pH or soil fertility can cause major problems for successful plant growth. Raised beds can overcome such limitations.
A raised growing surface allows certain specimen or trailing plants to be displayed to maximum effect.
Mobile containers can be particularly versatile. Wheeled outdoors in summer, they can display semi-hardy plants or summer bedding. Wheeled into a glasshouse or conservatory in winter, they are ideal for winter bulb, herb or pot plant displays.
Many raised beds, particularly some containers, are ornamental in their own right and can make a considerable difference to a garden's aesthetic appeal. On the other hand, when it comes to selling the house, poorly designed and poorly built specimens can be a distinct liability.

Where should raised growing areas be sited?

This deserves careful attention right at the beginning. Raised beds in the wrong position are of little value to plants or people. Here are a few guidelines to bear in mind to minimize the risk of this happening in your garden:

Seating. Provide opportunities for the passive enjoyment of gardening. Choose types of seating that suit you and integrate them as unobtrusively as possible into the overall design, perhaps even into the beds themselves for easier working.
Access to a water supply. This is essential, since containers and raised beds, particularly small ones, need frequent watering in dry weather. A standpipe, with provision for a wall-mounted hose reel alongside, is the best solution, although overhead, seep hose or trickle irrigation may be worth installing too.
Aesthetic considerations. Fit the garden area as naturally as possible into its surroundings!
Access. Provide safe access, preferably to all sides of the bed, using surfacing which is stable, level, non-slip and non-reflective. Well laid paving slabs, pavoirs, setts, bricks or concrete may be suitable. Make sure the paths are wide enough for you to use easily - especially when you are transporting tools, etc! Any steps or ramps should be very shallow, (maximum slope for wheelchairs 1 in 15), with handrails where needed.
Shelter, aspect, shade. Site the beds to take advantage of any existing shelter or shade, or provide shade as necessary. Avoid heavily shaded, cold or draughty situations which may limit plant growth and discourage active use of the beds. Minimise any uncomfortable glare from excessive areas of hard surfacing in bright sunshine by careful planting, screening and choice of hard surface materials. Accessibility. Generally, see that raised beds are sited to allow ready access to and from the house and other parts of the garden. To be able to see the garden area from indoors is a great asset - you can keep an eye on what is growing from the comfort of being indoors!

Matters of Design

The better the design, the better the garden. Before looking at the finer points of design, ask yourself a few basic questions:

What are your own needs? What height and width would you like? Will you be gardening while standing or sitting?
What plant material will be grown? Alpines or summer salad crops could thrive in a shallow small bed, for example, whereas cordon apples or large shrubs would not.
What can be made available in the way of construction materials and manpower skills? Certain opportunities and constraints are bound to appear here. Think broadly and be imaginative.
Aesthetically, what design would fit best into the garden site and its surroundings? Curved, irregular shaped beds of roundwood posts for example, are better suited to an informal environment than rectangular beds made of uniform-sized bricks.

Now to the detail...

Dimensions

There are no such things as standard heights, widths and sizes, since individual requirements vary so widely. But certain guiding principles are always valid.

Some people are more comfortable working at relatively low beds, or sitting down, possibly in a wheelchair, whereas others prefer to work at elbow level, standing up or leaning against the bed. Yet others require beds at several heights in order to minimize undue fatigue in any one part of the body. Bear in mind that low beds generally have more visual appeal - and are cheaper to construct.

The width of beds should always suit you with the tools you are. Ensure always that all parts of the beds are within comfortable reach. Naturally, beds accessible from two or more sides can be up to twice the width of those reached from one side only, or even wider if there is some permanent planting in the middle.

The overall size of a bed should be decided firstly in relation to the degree of use it is likely to receive. A small raised area, intensively used and well managed, is of far more value than a large area, much of which may be under-used or even neglected. Other factors to consider include the space available (including access room) and the scale and nature of the hard and soft landscape of which it is to be a part.

Seasonal or permanent?

Make sure that beds which will be moved indoors in winter are small and light enough to carry, and fitted with handles or mounted on wheels or castors. Mobile units allow the growing of a wide range of less hardy plants.

Footholes and knee-space

These can be designed in for extra comfort and access for those who have to work at beds facing forwards. The three main ways of providing them are to:

Extend the upper part of the bed as a cantilever.
Design the bed like a manger or tabletop.
Build the base of the bed narrower than the top.

Remember that some of these modifications will reduce both plant root run and the working surface available to the gardener. In addition, 'non-standard' building gets very expensive!

Aids for extra support

These are particularly useful if you cannot stand for long or have limited balance. Design them as unobtrusively as possible. Think about providing:

Handrails or handgrips sited appropriately.
Seating, possibly built into part of the edge of a bed or provided in the form of a wide stretch of strong coping.
A wide stretch of coping or sloping kerb for easy leaning or support.
Leaning or slumping posts, judiciously placed near the bed. Try and incorporate them naturally into another structure such as an archway or pergola.

Shape of the bed

Design the shape of the bed to allow you to use it with ease. An L-shaped curved bed may allow this as will carefully designed indentations. Some building materials are clearly more flexible in this way than others.

If you are visually impaired use strong contrasting colours in the design, and also different surface textures or constuction materials at strategic reference points (such as at corners or regular intervals along the length of the bed). This will help you identify where you are in the garden.

Attractiveness

Don't forget to:

Vary the colours, textures, materials, shapes, heights where appropriate.
Plan the design of the beds in the context of the garden of which they are part.

Construction materials

Many are available but before making your final choice, think about the following points:

Stability. Safety is crucial.
Strength. Large beds may hold large volumes of soil which exert considerable pressure on materials and so must be stronger than small beds. Extra bracing or other strengthening may be needed.
Durability. The life of different materials varies. An ability to withstand frost action will nearly always be important. Permeability to rain water may shorten the life of the bed unnecessarily and demand a protective coating.
Maintenance. Some materials are completely maintenance-free whereas others require periodic attention.
Cost, both of materials and labour. Compare these with those of obtaining a good set of special tools.
Construction skills required. Some materials require minimal skills, others are more demanding.
Surfaces. There may be a need for a particular colour or texture, or for a material with nonreflective or smooth, non-abrasive surface.
Aesthetic appeal. Where possible, the bed's colour, building material and style must blend harmoniously with immediate surroundings, Be imaginative - large expanses of monotonous brick or concrete slabs can look depressing.
Local planning regulations. It is worth checking on these where the garden lies in a conservation area, belongs to a listed building, or lies near a boundary or roadside. The height or type of building material may have to be modified.
The final choice of construction material is usually based on a compromise, taking the factors above into consideration. Careful thought avoids problems later on.

The most appropriate materials are often:

Stone. Prepared walling or natural stone, laid dry or using mortar. May be a very high or very low cost alternative, often depending on availability. Choose local stone where possible. Skilled labour required for construction. Foundations needed.
Brick. Durable, strong, low maintenance, construction requires skills. Foundations needed, also provision of damp proof course and lining of walls against house walls. Engineering or hard stock bricks give most professional finish but can be extremely costly. Domestic bricks are much cheaper but porous so must have coping of hard stock bricks. Use engineering bricks as footings to provide damp-proofing. Good range of colours and unit sizes available. Like stone, this material is very adaptable allowing for a wide range of bed shapes, both rectangular and curvaceous.
Pre-cast units e.g. concrete, fibreglass, reconstituted stone. Cheaper than brick or stone, except in the case of self-assembly kits. Visual appeal varies. Less adaptable than brick or stone.
Wood. Very versatile and adaptable - railway sleepers, strong floorboards, wooden posts, split logs, round wood, telegraph poles. Ideally, should be pressure treated. Buy ready-treated or, if not possible, paint, preserve and line the timber. This is essential for any parts to be embedded in the ground and up to two inches above ground level. Allow for free drainage of water from base of walls. Durability varies. Hardwood ideal but generally prohibitively expensive - treated softwood quite adequate. Cost varies, but depending on availability, wood structures tend to be much cheaper than brick. Carpentry skills required. Very wide range of alternatives possible.
Peat blocks. Useful, particularly for beds for lime-hating plants. Cheap, minimal construction skills needed. Easily damaged, but blocks replaceable. For longest life, build bed in shade or semi-shade, keep blocks damp. May last up to ten years, particularly where blocks become bound together by plant roots.
Soils, compost, drainage. Remember that plants growing in containers or raised beds have a comparatively small reservoir of nutrients and moisture to draw on, in comparison to plants growing in garden soil at ground level. The smaller the container the more vulnerable the plants are to moisture stress and nutrient deficiencies. The soil or compost used for raised areas must, therefore, be of adequate fertility and depth for the plants selected and provision must be made for supplementary feeding and irrigation where necessary. Free drainage of water from the beds is important. Provide it by ensuring that there are drainage holes at the base of any containers used and that several inches of coarse grade material are laid before soil is added. Beds standing on solid bases will need drainage holes in the sides.

The type of soil or compost used must be appropriate to the needs of the plants to be grown, for plant requirements in terms of soil fertility, drainage or pH vary widely. In most cases, a mixture of good garden soil and a proprietary compost is suitable for larger beds, and soil-less composts for containers. Do not forget that during the first year after planting, the soil level in the bed or container will settle and need topping up. It is wise, therefore, to plant annuals only in the first year.

And finally ...

Planting

Ask yourself these questions before deciding what plants to grow in a container or raised bed.

What level of maintenance and range of work is needed?
What times of the year will gardening be possible and impossible?
What gardening skill and knowledge is available? i.e. can only robust, hardy plants be grown, or more specialised, tricky subjects as well?
What environmental conditions will the plants be growing in? i.e. consider container size, soil depth, bed aspect, shelter and shade and select plants to suit these conditions.
What plants do you like or dislike growing?
What would you like to grow? Does this include material for flower arrangements, and crafts - or to eat?

Bear in mind that the plant kingdom has a very diverse range of characteristics to offer. These include rates of growth, size, form, hardiness, growth cycle, seasonal interest (flowers, stems, leaves, fruits), fragrance of flower and leaves, textures, colours, growth habit, edibility, nostalgia value, appeal for flower arranging.

Many different types of plants can be grown in raised beds and containers. Once the questions above have been thought about carefully, the final choice can be made from the following suggestions: seasonal bedding, herbaceous perennials and biennials, shrubs, alpines, bulbs, vegetables, plant material for drying or cutting fresh, herbs, climbers, conifers, heathers, specimen trees or shrubs, soft or dwarf tree fruit, water or marsh plants, plants for attracting wildlife.

A trellis provides protection from north winds and support for climbers and shrubs growing in the raised bed and for cordon fruit trees planted at the side of the bed. Indentations in the container break up the line and improve access to the growing area or provide a welcome spot for a seat. A tiered effect is created by a small peat bed within the raised garden, providing an opportunity to vary the type of planting. Evergreen shrubs are planted in the least accessible parts of the bed but all other areas are easily reached from one side.