Pools and Water Features
Many of the most beautiful natural rock landscapes have water as an essential part of their formation. Water is always fascinating, whether it takes the form of a rushing, tumbling waterfall or a still, calm lake. It can both soothe and excite the senses, and tempts people to just stand and gaze. The most obvious way of introducing water to your garden is in the form of a simple pool. Perhaps the most desirable position for the pool is as a feature of the patio, where you can see and enjoy it whilst relaxing outdoors or when sitting or working inside the house. If you decide to plan a pool as a feature of the lawn area, try to ensure that it forms an integral part of the design, and does not suddenly appear for no particular reason.
However, if the only suitable position for a pool is some distance from the house, this can have the advantage of encouraging people to go right into the garden, as they will naturally be drawn to the water.
The site for a pool should be in sunlight for at least half the day, and preferably the whole day. It should also be level and away from the overhanging branches of trees, for falling leaves will pollute the water and make a mess that is almost impossible to clear. Having planned your site, it will be necessary to consider the shape of the pool, and this should be determined by the line and style of the garden layout. A formal town garden would be the appropriate setting for a regular square, or rectangular pool, or a variation of these such as an L-shape or rectangle with curved, Roman-style ends.
However, if you want to combine your pool with a rock feature, building in a stream or waterfall, it should always be an informal, free-form shape. Curves should be bold and sweeping rather than forming intricate nooks and crannies. This not only looks better, but is more practical for the pool construction.
A depth of 18in will create a pool that provides a suitable environment forand water plants, but it is preferable to allow a 9in wide shelf around the inside perimeter, at a depth of 9in. This provides a position for marginal plants. The sides of the pool should slope slightly inwards.
Perhaps the simplest method of making a garden pool is the installation of a plastic pool liner. Liners are available in varying grades and forms of plastic material, including basic polythene, PVC or tough butyl, a synthetic rubber. Cost, durability and life of the pool will obviously depend on the quality of material you use.
The liner should be sufficiently large to fit the pool shape with a good overlap all round. Installation simply involves marking out and digging a hole of the required shape and size, and picking out any stones from the. The shaped soil should then be covered with a layer of sand.
Spread the liner over the pool shape and secure temporarily at the edges, using stones or small slabs, then start to fill with water (ordinary tap water is quite satisfactory). As the pool fills the liner should be allowed to ease in to fit tightly the excavated shape. It will be necessary to adjust the weights around the edges for this purpose. When the pool is full of water, trim any excess plastic so that there is an overlap of approximately 4in all round. The pool surround can then be paved, or disguised with rock stone where appropriate.
A more expensive form of pool construction is the installation of a pre-formed pool shape. These are made from rigid fibreglass or a more flexible plastic material. A good range of informal shapes is generally available, particularly from water garden specialists. The construction process is similar to that of a plastic liner pool, in that it is necessary to excavate a hole of the appropriate size and shape and line it with sand. The pool ‘mould’ can then be placed in the ground and filled with water, and the soil tidied and flattened around it. The pool edges should be disguised withor any suitable form of ground surfacing, in the same way as for the liner pool.
The construction of a concrete pool is a more complicated process. A hole should be dug to the required shape, as with the other methods, and this forms the basis for a floor and walls constructed from a 6in depth of concrete. The concrete mix usually consists of a combination of 3/4 in ballast and cement, together with a small quantity of waterproofing powder, which helps to counter the rather porous nature of the material. When the concrete shell is set, it is coated with a cement mortar render to a thickness of about 1/2 in. The entire process is best carried out in summer months, during dry weather.
The final stage of construction is the application of a sealing compound to neutralise the free lime in the concrete; this is most important for the survival of fish. If you contemplate the construction of a concrete pool, obtain as much detailed information as possible before you commence work.
A raised pool
Of course, a pool does not have to be at ground level. If yours is intended as a feature of the patio, why not raise the finished level to a height of, say, 2ft. It is pleasant and cooling on a hot day to have water close by, and almost everyone — particularly children — will be unable to resist the temptation to dabble their hand in the water. Where children are concerned, a raised pool can be considerably safer, for there is less danger of them falling whilst peering into the water.
The construction need not be complicated, and a plastic liner can be used. Build up two or three courses of brickwork using either ordinary clay bricks or a decorative manufactured block. Fit the liner in the pool shape, and secure the overlap by fixing a row of bricks, laid side by side rather than end to end, or a manufactured coping stone. One or two manufacturers of paving and walling products market a raised pool in kit form, and this can be more straightforward for the less confident do-it-yourselfer.
Having tackled the basic pool construction, you will want to turn your thoughts to the finishing touches that will create a worthwhile water feature, and a really decorative asset to your garden.
Water plants are one important aspect of these finer points, but you should allow the water in a new pool to settle for a few days before introducing plants. When it comes to choosing the plants, you should go to a garden centre with a good aquatic department or to a water garden specialist, who may also sell by mail order. Such companies often offer a collection of plants, and this assists in ensuring a balanced environment in the pool.
You will probably find that the plants are sold planted in small, plastic mesh baskets. These can be placed directly in the pool, and the plants will remain in them and become established. This method eliminates the need for a layer of soil in the base of the pool. The best time to plant is from June to September.
There are plants to fulfil various purposes in the pool, and each should be allocated its proper position.
Marginal plants growing in the plastic baskets should be positioned on the shelf around the edge of the pool. These will, in fact, grow in either wet soil or water up to about 6in deep. Plants include marsh marigold, cotton grass, which grows 12in high and is topped by fluffy white tufts, many moisture loving varieties of iris and Lobelia cardinalis, a striking plant with bright redon stems about 2ft tall. Deep marginal plants are totally submerged in their baskets, and include the water violet, with its mass of lavender coloured flowers. Water are probably the most familiar of aquatic plants, but they should be placed sparingly in the pool, as each plant requires approximately 25 sq. ft of water surface. Plants should be placed in their basket on bricks initially, and gradually lowered as they mature and the stems grow longer. A wealth of beautiful flower colours are available. ‘Alba’ is a favourite white variety and ‘Rose Arey’ has delightful, deep pink, scented flowers. Of the red flowering varieties ‘Escarboucle’ is superb, and ‘Sunrise’ has large, golden yellow blooms.
Floating plants are placed on the water surface. Among more common types are the various forms of duckweed, but for something unusual the water lettuce (Pistia stratoites) has great appeal. The plant resembles a lettuce with thick, attractively shaped leaves, but it is not hardy and should be kept indoors during winter months.
The final, and perhaps most important, group of plants is the oxygenating plants. These are the forms of ‘water weed’ that ensure clean, algae-free water, and are an essential feature of any garden pool. The plants can be bought in bunches, and the stems should be pressed into soil in a basket. They will soon take root and become established of their own accord.
Fish for your pool
A selection of water plants will help to create the right conditions in the pool for ornamental fish. Goldfish are the most common choice, but there are many other types that will live in coldwater pools. These include Shubunkins, which may have a mixture of red, yellow, blue, brown or even violet coloured scales. Golden Orfe swim near the water surface so that they can clearly be seen in summer months, and a more recent introduction is the Japanese Koi carp, a beautiful fish that can grow to a large size, and is therefore better suited to the larger pool.
As a general rule, you should allow a 2in length offish to every square foot of water surface in a new pool, and they can be introduced to the pool about two weeks after the installation of plants. The fish should be fed for the first few months with a proprietary fish food, and thereafter feeding during autumn and spring only should be sufficient.
It is surprising how tame fish can become, particularly if they are fed regularly at the same time every day, when they may even become sufficiently bold to eat out of your hand.
If they are given the right pool conditions, fish will generally remain quite healthy. However, they are unfortunately susceptible to a number of diseases if the water is polluted by surplus uneaten food, decaying leaves or even garden chemicals. It is therefore important to avoid both pollution of water and simply putting more fish into your pool than the volume of water will support. An additional safeguard is to purchase your fish from a reputable supplier, so that they do not introduce disease from the outset. Furthermore, the introduction of molluscs, or water snails, will also be of benefit in keeping the pool water free from decaying matter.
Fountains and waterfalls
is always fascinating; it looks refreshing and the sound has immense appeal. A fountain can make an attractive focal point. Whilst there is no scope in the average garden for an impressive column of along the lines of the famous landmarks of Versailles or even Trafalgar Square, it is not difficult to install a modest fountain that will give equal pleasure on a somewhat smaller scale.
The most common misconception regarding fountains is that a constant supply of running water must be on hand. In fact, all that is needed is an electric submersible pump to circulate the water. The principle is quite simple. A lead is plugged in to an ordinary earthed three-pin socket indoors in a position convenient for access to the garden. An extension cable leads into the garden via a transformer, which reduces voltage to a low level for safety. In the garden the cable is joined by a weather-proof connector to a sealed electric cable. This cable is connected to a small pump, which operates silently, completely submerged under the pool water.
The weatherproof connector can be covered with a piece of timber or a small paving slab, to enable easy access should the pump have to be disconnected, thus avoiding the need to disturb the extension cable.
A fountain attachment is fixed on top of the pump, and will create a jet of water — usually adjustable in height — by circulating the water in the pool. No other water supply is needed, although during hot weather you may find that it is necessary to top up the pool to compensate for the slight volume of water lost through evaporation. If you have a very small patio pool, a fountain may cause problems when there is a breeze, since the water will be borne by the breeze and may splash beyond the confines of the pool itself. The answer here is a small bubble fountain, which takes the form of a low globe of water safely confined within the pool.
A further possibility for a restricted space is the installation of a gargoyle fountain. A raised pool should be constructed immediately in front of a vertical wall, into which a gargoyle ‘mask’ is built. Many garden and aquatic centres sell these in the form of a lion’s head or dolphin spout. The submersible circulating pump is positioned in the pool and is fitted not with a fountain attachment, but with a length of plastic tubing which leads to the gargoyle spout, and is built in to the wall. The pump then circulates the pool water through the gargoyle fountain, creating an attractive feature at eye level.
A fountain is not the only feature that can be created by the use of a submersible pump. A waterfall is a more ambitious project, but its appeal springs from the natural and irresistible movement of sparkling water dancing and splashing over solid rock stones.
A waterfall or stream should be integrated with a pool, and should be constructed so that the water springs — apparently from a rock — at a point some three to five feet higher than the pool itself. It is possible to use a pre-formed fibreglass waterfall chute, but these do tend to have a rather rigid and unnatural appearance. A more flexible design can be achieved by the use of a plastic liner or even a concrete base. A submersible pump is once again used to circulate the water from the pool, through plastic piping to the head of the waterfall; this is buried just beneath the surface of the soil beside the stream.
There are several design points to consider when planning the course of your waterfall, and the positioning of rock. Firstly, the path should not follow a straight line, either vertically or horizontally. Stagger the fall in steps, and stagger the path so that it appears to meander through its surroundings.
Choose carefully the stone over which the water finally falls into the pool. A large, dished stone 2 to 3in thick is ideal, and this should overhang the edge of the pool. If the edge of the stone itself is smooth, a level sheet of water will cascade from it, but if the edge is grooved and irregular, the water will bounce and splash as it falls, creating a more informal effect. The path of the water can be broken by small pieces of rock and large pebbles, so that it tumbles and splashes off them.
The sound of the waterfall will probably have as much appeal as its appearance, and this is governed by the depth in the pool. Shallow water will produce a light, tinkling sound and deep water a deeper, more resonant tone. If there are fish in the pool, ensure that they have sufficient space away from the moving and white water.
Plants for the waterside and damp positions If your garden has no open area that is suitable for a pool, it is possible to grow moisture-loving plants in a damp and partially shaded position. They would be equally suited to the damp ground beside a pool or stream. Their flowers and foliage will soften the pool surround and their reflection in the water of the pool will add an extra dimension to its beauty.
Some of the most suitable plants include:
Astilbe. Flowers are delicate, feathery plumes on long, slender stems 2-3ft tall, and appear in summer. Colours are red, pink and white.
Astilbe chinensis is a miniature variety, just 8 to 12in tall, with deep purplish pink flowers. Gunnera manicata. A magnificent plant with vast, flat leaves similar to those of rhubarb. Strictly for large gardens, as a specimen can grow to a massive size, often approaching 10 or 12ft across.
Hosta. A superb plant that thrives in any damp, shady position in the garden. The leaves are the main feature of interest, being large and flat and excellent for flower arranging. There are many varieties, perhaps the most familiar being Hosta fortunei, with delicate green leaves, and Hosta sieboldiana, with darker, bluish green leaves with a deeply ridged surface.
Iris sibirica. This herbaceous form of iris grows to a large clump of narrow foliage with white, blue or purplish flowers, 2 to 3ft high. Flowers appear in summer.
Primula. There are several moisture loving types of primula suitable for the edge of the pool. Perhaps the most notable forms are Primula denticulata, with beautiful round flower heads, mauve or white, and Primula florindae, with yellow flowers on long stems 2 to 3ft high, and foliage with the subtle aroma of cloves.
Rheum palmatum ‘Rubrum’. A plant with large, reddish leaves of real architectural value. It should be grown individually as a specimen where space permits, since it can grow to 4 or 5ft high.