Water Gardening

What is water gardening?

A pond with aselection of water plants

Nothing can quite transform a garden landscape like a water feature. Whether it's a dramatic waterfall or a quiet water pond, garden water features work magic on any garden landscape, providing a focal pointand soothing the soul. Moving water provides delightful background music and masks traffic noise. There is something about the sight and sound of water that attracts and fascinates people. In fact water is just short of hypnotic. Not only people, but also wildlife is drawn to garden water features and garden ponds. The type of wildlife depends on the size of the water feature in your garden. The sight and sound of water has always drawn the interest of people. Garden water features add an appealing element to a garden.

Water gardens can include garden fountains, waterfalls, and small garden ponds and elaborate combinations of rockwork and landscape lighting. From the glitter of a sunbeam reflecting from the water, the tinkle of a tiny garden fountain, the scent of a beautiful tropical water-lily, to the lazy lacy motion of a long finned koi, every sense is both stimulated and soothed by a garden pond. It invites you to sit down and to reflect with it, making water gardening very desirable.

Apart from being fascinating and hypnotic, water features have always been a basic part of gardens from the earliest times. Water gardens date back to the Babylonians and Egyptians who used them as the focal points of their courtyards. This tradition continues today. A small water garden adds a cool, lush look to the garden landscape with less effort than a "planted in the soil" garden twice the size. A natural pond creates the feel of tranquility and calmness. A well-designed reflecting garden pond will be an asset to any garden as it has the ability to transform an ordinary garden into an extraordinary showpiece. Recently garden water features and water gardens in particular have become very popular and the market is overflowing with different types of garden ponds and other water features for the garden. We are so spoilt for choice; there are flexible plastic liners, inexpensive water pumps, pre-fabricated garden ponds, cascades, water plants and fish to choose from.

The creation of this tranquil little water garden within an existing garden is not difficult. There are as many ways to accomplish it. It can be tiny, maybe even in a container water garden on the porch or patio. It can be huge, a natural bottomed wetland environment, filled with wildlife, both visiting and resident. Birds, dragonflies, butterflies, frogs and even the occasional fox have been observed to visit water gardens in urban neighborhoods. For most of us the size of the water garden is somewhere in between, and the planning and building of garden water features can be as much of a joy as the end result. It really does not matter whether you have a small townhouse garden, balcony, patio or large garden, there is sure to be a water feature of the correct size, shape and style to suit your needs and desires. Even the smallest imaginable garden (a small fountain on a table top for instance) can be enhanced with a micro water feature and the appropriate plants and accessories.

In this section we aim to provide you with enough guidelines to create your very own garden pond, water feature or water garden.

Formal and informal garden ponds

When making a decision on the garden pond you also need to consider formal garden ponds versus informal garden ponds.

Formal garden ponds

Formal ponds can be classical depending on the style and architecture of the house and the available space. One characteristic of formal garden ponds is that the construction material used normally consists of durable materials such as bricks, cement and tiles. (Due to the popularity of garden ponds these days you also get formal and classic garden pond moulds.) When designing formal garden ponds you need to remember to:

Keep the design simple and uncluttered.
Follow geometric lines and pay attention to symmetry.
You may add a focal point like an ornamental garden statue or garden fountain.
A garden fountain can be multi-tiered, placed symmetrically for a classic style or asymmetrically for a modern take on formal garden ponds.
You require a well-defined border or edging for formal garden ponds.
Enhance the look of the formal garden pond with either symmetrical plantings, columns, arches, trelliswork or containers.

Informal garden ponds

The informal garden pond is not bound to form and can thus be free-form with gentle curves and no straight lines. You have a limitless option regarding size of informal garden ponds as long as it does not dominate the garden landscape. Informal garden ponds also tend to be more affordable than formal garden ponds in that you do not require the expensive cement-construction. Instead due to the plethora of products available from garden centers and nurseries these days you can make use of black plastic sheeting, pre-fabricated plastic or fiber-cement moulds. Examples of informal garden ponds also include natural garden ponds, the bog garden, a garden fountain, and of course pre-fabricated garden ponds with or without waterfalls. Water features and focal points in informal garden ponds can also include millstones, rock-pools, glazed pots, and so forth. Most of all no visible borders, the waterfall or bog garden must look as if it has been lifted out of nature and carefully placed in the surrounding plants and rocks, and the like, in your garden.

Planning your water garden

Plan your water garden using some basic principles. Do take into account the following basic points when making a decision and your ability to cope with the maintenance work that goes hand in hand with having a water garden. Small garden ponds are best for small properties. A container on a deck may be all that is needed and add just the right feature for your space. Water features like waterfalls, rockwork, lighting and garden fountains depend on your budget, style of your landscape, and purpose of the garden pond. All garden ponds regardless of size will need maintenance throughout the year. With proper planning you can ensure a healthy balance between living and decorative features of a water garden that can almost care for itself with simple maintenance inputs from you.

Location of the garden pond

Choosing the correct position for your garden pond is perhaps the most important decision that needs to be made when designing a water garden. The majority of water flora and fauna, such as fish need plenty of sunlight. A site that gets a minimum of 6 hours of direct sunlight would be best suited. One should also take care not to select a site that is too close to tall shrubs or trees. Above all the position of your garden pond will depend on its style and function. It just seems pretty obvious that you would want to show off your garden pond and you would thus choose a site that is clearly visible from where you spend most of your time, and if you want to hear the sound of water you would prefer to have your water feature near your living area, or if you want to attract wildlife to your water garden you will most probably choose a secluded, low-lying and sunny area in your garden.

Style of the garden pond

The style choice that you make will also depend on the size of the garden water feature that you want and the purpose that the water feature is to serve. Your garden dimensions will also dictate the size of your garden ponds. This is mainly because garden ponds must complement the garden and not dominate it. Questions that you will need to ask yourself would be: Do you want formal water features, natural water features like a bog gardens, or a small water features like a millstone? In all these cases the available space and the style of the house and the garden will play a determining factor.

Garden ponds and the availability of water and electricity

Periodic refilling of the container and a garden hose should be easily accessible to counter the effects of evaporation. If using a pump to power a fountain, waterfall or filter, a household circuit plug (110 volts, 20 amps) made for outdoor use should be near the garden pond. The local regulations that govern your neighborhood can also play a major role. Before installing an in-ground garden pond, check with your local building department for restrictions and the possible necessity of having a permit. Always consult your local utility companies for the location of underground lines before digging.

The microclimate of the garden pond site

The microclimate that exists in your garden needs to be taken into consideration. Does the intended site for your garden pond get full sun or is it in the shade - Sunlight conditions. Most water plants need a spot with 5 to 8 hours of sunlight. A shadier spot can be used, but it will limit your choice of aquatic plants. Garden ponds with a water holding capacity of less than 380 liters (100 gallons) do better with afternoon shade.

Is it very hot or cold? If you want water lilies you will require a minimum of 6 hours of full sun. If you want to keep Koi you will require some shade in addition to full sun.

The soil on the intended garden pond site poses a few limitations in terms of water drainage. If building a garden pond, the soil in the site should be well drained to avoid shifting or settling that can crack or break the lining. Low areas with water runoff from the surrounding landscape should be avoided.

Another limiting factor that should be taken into account is trees. You should reconsider if the site of your garden pond is under overhanging trees. The falling leaves in case of trees that are not evergreen can decay in the water, harming fish and plant life. They may also clog pumps and filters. Placing an in-ground pond too close to a tree may damage the tree's roots.

Which features to add to the garden pond?

When making a decision on water features that will enhance your garden pond, the site and function of the pond will help to determine whether you choose a statue, waterfall or a garden fountain or simply just water plants. A natural slope will lend itself beautifully to waterfall type of water features that flow into one or more garden ponds.

If you choose readymade water features then you should also take your budget into account. There is a quite a wide range available from small to medium sized water features. There are also small pre-cast ponds, garden fountains, wall features or waterfalls that are made out of materials ranging from plastic to realistic looking concrete. These are all usually very easy install and often come with all the necessary attachments to make them work. On the other hand you can also dispose of these easily if you tire of them. Larger water features are more complicated and will require very careful planning to avoid mistakes.

Maintenance requirements

Any garden pond, regardless of its size needs to be maintained at different times of the year even though it is easily thought of as a self-contained ecosystem. This maintenance will include clean-up in the spring, periodic removal of debris and replenishing of the water, plant care, protection from leaves in the fall and preparation for winter. Decorative water features will need to be periodically cleared of leaves or other debris.

When choosing aquatic plants, keep in mind that the plants should cover no more than fifty to sixty percent of the water surface. There are many types to choose from. Some are free floating while others are marginals to submerged. Selection depends on the size of the water pond and the kind of look you want. Water lilies can add drama and fragrance even in small tubs. Some plants provide oxygen and help keep the pool healthy. Fish can be a beneficial addition, because they are good scavengers, cleaning up debris. They also can help control mosquito larva, and other insects.

Monetary consideration

The amount of money, that you have available to spend, will also determine the type of water feature that you install in your garden pond. It is simple: the more complex the feature, the more it will cost. Complex water features that include a waterfall and garden fountain will obviously cost more than simple plastic lined natural garden ponds. Also take into account hidden costs such as electricity to keep the pump running and increased water usage to keep the reservoir of water features full.

Aquatic plants in the garden pond

Water Lillies (Nymphaea spp.)

Once you've chosen the type and style of your garden pond, the next consideration is plants for it. Do visit a garden center in your area that specializes in or is knowledgeable about aquatic plants. They will be able to help you make the right plant choices for your locale. Maintaining a healthy garden pond which is clean and clear, with the correct balance between water plants and algae is essential. The water plants will compete with the algae for nutrients. These nutrients come from the fish droppings and nitrogen from the rotting plant material. Algae growth can be kept in check by shading at least half of the garden pond to prevent the sunlight from encouraging algae growth.

There are many types of plants available for use in a garden pool. Considerations such as water depth, amount of sunlight and how each species relates to its surroundings need to be taken into account when choosing plant material. Both floating leafed and submerged plants are needed for a healthy garden pond and should be included in your selection. Water garden plants are called aquatic plants, because their life cycle revolves around water. Aquatics plants come in different types such as: emergent or marginal plants; submerged or oxygenating plants; and floaters, the so-called ground covers in garden ponds and marsh plants. (Tip: Only introduce fish in your garden pond once the oxygenating plants are established because the fish will destroy them as well as the balance in the garden pond.)

Submerged / Oxygenating plants

Oxygenating plants, or submerged plants are important as they are responsible for the food, shelter, oxygen and spawning medium for fish. Oxygenating plants are also commonly known as pondweed. They are anchored with coarse gravel in mesh containers and will grow quickly and establish roots if left undisturbed. Because they are fast growers and rarely protrude above the surface, they will need thinning in smaller garden ponds. These aquatic plants are important in maintaining the quality of the water in garden ponds. They produce oxygen for use by both plants and fish. By utilizing nitrogen produced from decaying plant material and fish waste products, they deprive algae of nutrients. (Tip: It is best to cage these plants if the garden pond contains fish which tend to forage on submerged plant foliage.)

Nine to ten bunches of oxygenating plants per square meter (5.8 feet square) of pond surface will be sufficient to keep a garden pond healthy. Following are a few examples of oxygenating plants that can be used in garden ponds:

Hornwort (Ceratophyllum demersum) also known as Marestail. Dark green, non rooting plant that doesn't float or sink - just settles in the water. It will thrive in deep, cold and shaded ponds and will provide an area for fish spawning.
Fanwort (Cabomba Canadensis) Dark green bristles on thin stems. Flowers mid- to late summer are white with yellow centers. It has bright green fan like foliage. Fish tend to use them to spawn and fry will find shelter in the leaves. Fanwort will grow in sun to shade in water that is 15 to 30 cm (6 to 12 inches) deep.
Jungle Vall (Vallisneria sp.) also known as Wild Celery. This plant has linear green, ribbon-like, translucent, pale-green leaves. It will grow in shade, part-shade and sun in water that is 15 to 60 cm (6 to 24 inches) deep.
Anacharis (Elodea Canadensis and Elodea crispa). Elodea or Anacharis is a very good producer of oxygen and forms sturdy stems covered with curled leaves with occasional white flowers on the surface. It is also a dietary supplement for fish.
Pondweed (Potamogeton spp.) This plant has branching stems with long leaves and is larger-growing than the other types of oxygenating plants.
Water Crowfood (Ranunculus aquatilis) This plant has very fine foliage underwater and lobed leaves on the surface. In spring it will bear small white flowers.
Milfoil (Myriophyllum spp.) also known as Parrot's feather. This plant is a prolific grower.

Emergent / Marginal plants

Emergent plants are sometimes also called marginals or marsh plants. These plants are grown along the edges of garden ponds where the roots are attached to the muddy bottom and portions of their stems are above the water. Some of them are even planted in water up to a depth of 20 cm (7.8 inches). It is very important to choose the right plants to suit the size of your particular garden pond. Roughly one-third of the pond margin should be covered with marginal plants to have a balanced effect. Emergent plants are usually placed so that the top of the pot is at or barely below the water level. Bog plants are also considered to be marginals. There are many different species of bog plants with varying heights, textures and foliage colors that add height and drama to water gardens. Following are a few examples of emergent plants that can be used in garden ponds:

Variegated Water Celery (Oenanthe Javanica) This is a hardy Marginal plant with leaves that are variegated with pink and white. It also has bare roots and grows between 15 and 30 cm (6 and 12 inches) tall. The planting depth is 0 to 15 cm (0 and 6 inches) in full sun to shade.
Cardinal Flower (Lobelia cardinalis). This plant sports bronze colored foliage with red to crimson flowering spikes from mid to late summer. These are slender plants that grow to height of 90 cm (36 inches) and will tolerate between 2.5 and 5 cm (1and 2 inches) of water. This is a great plant for adding color contrast to water gardens.
Dwarf Cattail (Typha latifolia). This is a small plant that reaches a height of 90 cm (36 inches). Walnut-size catkins. It can tolerate up to 15 cm (6 inches) water depth.
Zebra Rush (Scirpus tabernae-montani Zebrinus) These plants have segmented stalks with horizontal green and white variegations. The Zebra rush can reach 60 and 120 cm (24 and 48 inches) in height.
Horsetail Rush (Equisetum hyemale). Also known as scouring rush. This plant has dark green segmented stalks and grows to about 90 cm (36 inches) in height. It is a vigorous grower and spreader and will tolerate damp soil to 30 cm (12 inches) water.
Water Canna (Canna americanallis variegate) This is a plant with leaves that are orange with yellow stripes. It is a true aquatic canna hybrid. Long slender spade-shaped leaves. It has beautiful spikes of brilliant colored flowers. The plant itself reaches 1.2 to 1.8 m (4 to 6 feet) in height and will grow in up to 15 cm (6 inches) of water.
Pickerel Rush (Pontederia cordata) or Pickerel weed or arrow-leaf weed as it is also known. This is a lovely plant with glossy green foliage, bright lavender flowers. It is quite easy to grow in water gardens and will flower in autumn.
Variegated Sweet Flag (Acorus calamus 'Variegatus as well as Acorus gramineus) This is a grass-like perennial with beautiful green and cream striped foliage that persists all summer. Leaves are sweet scented when broken. This plant does excellent in sun or shade.
Black Magic Taro (Colocasia esculenta) which is also known as the Elephant ear. This is an incredible plant with dusty charcoal black leaves on dark burgundy to black stems. It can be classified as a tropical marginal plant. It grows to a height of between 7.5 and 15 cm (3 and 6 inches) and can be planted in water between 0 and 15 cm (0 to 6 inches). It will thrive in partial shade to shade conditions.
Arrowheads (Sagittaria latifolia) This is a plant with attractive, green arrowhead shaped leaves. White blooms in the summer. It grows from 30 to 120 cm (12 to 48 inches) tall. Arrowheads will tolerate sun to part shade.
Blue Flag Iris (Iris versicolor and other Iris spp.) These plants include the Louisiana iris, the Japanese iris and the yellow flag irises. This plant bears mixed blue flowers in June with grass like foliage. Grows from 60 to 76 cm (24 to 30 inches) tall and will tolerate full sun to part shade.
Dwarf Papyrus (Cyperus isocladus) Also known as Sedge grass. This plant is a perennial clump-forming plant with a green grass like foliage with "starburst like" flower-heads that turn brown in the autumn. Grows 30 to 45 cm (12 to 18 inches) tall and tolerates sun to part shade.
Water Blue Bells (Ruellia brittoniana) This plant has green grass like foliage that grows between 60 and 120 cm (24 and 48 inches) tall. It bears blue flowers in summer that is reminiscent of Petunias. It can tolerate sun to part shade.
Cork Screw Rush (Juncus effuses) This plant has interesting twisted and curled stems and grows to approximately 60 cm (24 inches) tall and tolerates full sun to part shade.
Gennera manicata is a deciduous perennial with enormous leaves and brown flowers.
Water forget-me-not (Muosotis scorpoides). This is a spreading perennial with gorgeous light blue flowers during summer.
Cat's Whiskers (Scirpus cernuus as well as Scirpus lacustrus) This is a densely tufted rush-like plant that would be ideal for smaller garden ponds.
White Arum Lily (Zantedeschia aethopica) This is a lovely, outstanding marginal or emergent plant with lush green foliage and striking white flower spathes.

Deepwater plants

Deep water plants occur further from the edge, between shallow and deep water, are other emergent plants where roots are attached to the bottom, but have floating leaves above the water. These plants usually have their leaves floating on the surface of the water and are essential in the maintenance of the correct balance in the garden pond. These plants shade the water and prevent the sun from reaching the algae; they also provide shelter for fish and other small animals. Above all they are very ornamental and dramatic. These plants like to be planted up in a heavy soil without any organic material. (Organic material would only encourage algae to grow.) It is a good idea to make use of special mesh containers to plant deep water plants in. You should cover the soil surface with coarse gravel or small stones to prevent the fish from removing the soil. A good balance can be achieved by planting one plant for every 2.5 square meters (26 feet square) of pond surface. Following are a few examples of deepwater plants that you can use in deep water gardens:

Water Lilies (Nymphaea spp.) These are the most beautiful of the water plants in my opinion. Flowers colors range from yellow, blue, white, and pink to red. There are many different varieties and some grow vigorously, while others require shallower water and a smaller area. For most the best water depth would be between 30 and 80 cm (12 and 32 inches).
- 'Red Flare' - A tropical night blooming red water lily with maroon leaves.
- 'Tetragona' - A hardy miniature white water lily with freckled leaves.
- 'Joanne Pring' - A hardy miniature pink water lily with green leaves and deep edge.
- 'Helvola' - A hardy miniature yellow water lily with freckled leaves.
- 'Hilary' - A tropical day blooming pink water lily with green leaves.
Pondweed (Aponogeton distachyos) This plant has dark green, strap-like leaves and bears scented white flowers with black anthers. These plants will thrive in water that is between 20 and 60 cm (7.8 and 24 inches) deep.
Golden Club (Orontium aquaticum). This is quite a versatile plant with white stemmed flower spikes with many tiny yellow flowers that appears in spring and early summer.
Lotus is also a dramatic addition to a garden pond. Both water lilies and lotus prefer full sun.
- The 'Momo Botan' Lotus Grows to a height of 60 cm (24 inches) and offers rose blooms from late winter through spring.
- The 'Wan-er Hong' Lotus Grows to a height of 30 cm (12 inches) and offers white blooms from mid winter through spring.

Though most are not grown for their flowers, some like lotus and water-lilies, are extremely dramatic and a feast for the eye when in flower. Bog plants are available for those not able to locate their garden pond in sufficient sunlight to support plant growth. Some bog plants can survive in locations that have as little as three hours of sun and still provide interest to water gardens.

Floating plants

Floaters are not rooted in the soil, but are allowed to float freely above or below the water surface. They are not as effective as the oxygenators but do not require anchorage. Floaters enhance the display of water lilies and lotus as well as adding a finishing touch to the water garden. They are the so-called ground covers of the garden pond world. They may be restricted by a framework to prevent them from moving around or allowed to float freely with the breeze. This produces an ever-changing look to the water surface. Some floaters are very prolific and may need to be kept in check by scooping out excess plants on occasion. If you do not keep it in check you will soon find that they become pestful like a weed.

Water Hyacinth (Eichhornia crassipes) This Amazonian plant has shiny green leaves with stems that expand into pseudo bulbs. It bears orchid-like lavender flowers. Long, bushy roots provide fish with a location for spawning.
Water Lettuce (Pistia stratiotes) This is a free-floating tropical plant that resembles floating lettuces with more intricately patterned than common water lettuce and a better overall plant with a compact growing habit. It has a tuft of long fibrous roots that trail beneath the plant itself.
Sensitive Plant. Creeping plant whose leaves close upon touch. Planting depth: 7.5 to 20 cm (3 to 8 inches). Full sun to partial shade. Yellow flowers in summer.
Parrot's Feather (Myriophyllum aquaticum) This is a South American plant with pale green, finely divided, feather-like foliage. Roots provide spawning area for fish.
Water Fern (Azolla spp.)This plant is also called the Floating Fairy Moss or Mosquito fern. The foliage is a lovely red to purple tint during autumn.
Giant Velvet Leaf (Salvinia longifolia and Salvinia molesta) This plant is also sometimes called Kariba weed or Water-spangle. It is an unusual floating fern with pale green round hairy leaves.

Algae are another plant type that is found in most garden ponds. There are hundreds of species of algae that can grow in garden ponds. Generally algae attach itself to the sides of the garden pond and remain innocuous. Some species of algae, namely the dreaded 'blanket weed' can grow up to a foot a day under ideal conditions and can rapidly clog a garden pond. On the other hand free floating algae is microscopic and is what causes pond water to appear green.

Water gardens need a mix of aquatic plants to attain a balanced system. You need to ask yourself the following: What look do you want? Do you want colors and textures, tall or short, lily pads and flowers or a combination of all?

Installing a garden pond

This section will guide you through the most cost effective way to install your very own water garden pond.

Use a rope or hosepipe to outline the shape of your water garden pond.
Make use of a simple design as a shape with too many curves and corners is not suitable as it results in wastage of lining material and might not even look pleasing to the eye. The principle of simplicity in landscape garden design is the best to follow in this instance.
Calculate the size of the liner by measuring the maximum width and maximum length and add twice the maximum pond depth to both the length and the width of the garden pond. Say for example you want your garden pond to be 2 m (78 inches) wide, 3 m (118 inches) long and 50 cm (19.5 inches) deep then you will require a liner that measures approximately 3 m x 4 m (118 by 157 inches). Remember to add the overlap for the rim edging to both the length and the width. (Tip: Use a garden pond size that will correspond with the standard garden pond liner width.)
Mark the garden pond outline with sand and start to dig the hole. Start the digging in the middle of the garden pond to the required depth. (Tip: A depth of 50 cm if you intend having fish and water lilies.) Make the planting shelf – about 20 cm (7.87 inches) deep and wide from the rim – around the edge if you intend having marginal water plants. Do shape the sides with a slight slope to prevent garden soil from falling in.
Ensure that the rim of the garden pond is level on all sides. Make use of a straight edge or plank that is long enough to reach the rim all round. Place a spirit level on the plank or straight edge and adjust till you are sure the rim is level.
Prepare the rim for the edging that you want. Remove all protruding stones and roots and fill the hole with soil.
Line the surface of the hole with a 5 cm (2 inches) layer of damp sand. (Tip: Line the bottom with undercarpet felt or even an old carpet.)
Spread the liner over the hole very carefully and in the center. Allow the plastic liner to touch the bottom of the garden pond. Refrain from standing on the liner. (Tip: Do this part on a hot sunny day because the liner will then be much more flexible and easier to work with.) Do retain a minimum of 20 cm (7.87 inches) all round for the rim edging. Prevent the liner from shifting position by carefully placing smooth stones around the top.
Fill the garden pond with water. Smooth the liner and tidy out all pleats as the water level rises. Close off the water supply when the garden pond is approximately 10 cm (4 inches) below the rim.
Complete the edging of the rim by laying slabs or smooth stones on the prepared rim. Alternatively you can bury the overlapping liner edge to a depth of at least 10 cm (4 inches) in a shallow trench. Cover the lining or plastic sheeting completely so as to protect it from the harsh ultra-violet rays of the sun.
Place the pump and fountain or waterfall in the garden pond and finish it off with water and bog plants. The moving water and the water plants will help to keep the water garden pond clean. In the beginning the garden pond will appear murky, but this will change as the water plants establish themselves in the garden pond.
Fill the garden pond with water to the top.
Only introduce fish into you water garden pond when you are sure that the aquatic plants are established.

Useful Tips and Tricks

The following are useful tips and trick to consider when planning your garden pond. They are also useful when it comes to maintaining you garden pond as a water garden requires quite a bit of maintenance to keep it looking healthy and inviting.

The water garden pond should be in full sun. Nearly all aquatic plants associated with water gardens need some direct sunlight to flower especially water lilies. Your dream of those beautiful water lily plants will come to nothing if you starve them of sun.
Ensure your water garden pond or water garden feature (it could be a simple garden fountain or stream or waterfall disappearing below ground) is away from trees especially deciduous trees that lose their leaves in Autumn or prevailing winds that may carry poisonous leaves into the pond.
If you do want trees the following trees can be grown close to water gardens - the Swamp Cypress(Taxodium distichum), and for frost-free areas the Powder-puff tree (Barringtonia racemosa), the old favorite Japanese Maple tree (Acer palmatum) and the Lagoon hibiscus (Hibuscus tilaceus).
Smaller water garden ponds can be netted against the worst of the autumn fall and a few leaves don't harm a healthy pond. However particularly avoid Willow, Elder, Poplars, Laburnum, Yew and Oak.
Make sure your water garden pond is not over-exposed to the prevailing winds.
Try to avoid any boggy waterlogged areas since this could result in your garden pond lifting.
Consider accessibility to a water supply. The water garden pond will want regular top-ups in the summer.
If there are to be waterfalls, streamed or garden fountains in the garden landscape, consider the distance to plumb in electricity, since this can be a major expense.
Consider SAFETY and children. Where there is water and children, at some point the children end up in it. Generally head first.
Partly for the reason above, but also because we spend so much of the year looking at our gardens from inside our houses, it is advisable to have a view of the water garden, the garden pond or other water feature or at least part of it from the house.
Check for bedrock, pipe-work, electricity or septic tanks where you have chosen to have your water garden.