Back to Info Sheets	How to Build a Water Garden   Remember the following points when determining pond size and location. 1.  A pond should receive at least 5-6 hours of sun a day, if you want lilies to bloom.  If the pool is in the sun all day plant Grasses, Bushes and Shrubs around the outside edge. 2.  Protection from strong winds is necessary. 3.  The site should not be to close to deciduous trees. 4.  Access to electricity is necessary if you're using a pump or lighting.  So plan as much as possible before you dig. 5.   Planning and building codes may restrict location, depth, enclosures, etc.  Check with your municipal department before beginning any constructon project.   CONSTRUCTION: Lay out the intended pool shape using a hose.  Mark the outline with wooden pegs hammered into the ground.  Overall the shape should have smooth and uncomplicated lines without sharp corners.  It is also good to peg out your deep water zone and consider where you would like a shelf left for optimum viewing. The shelf should be about 10" wide for placement of marginal plants.  If you intend to use a pump or operate night lights consider the placement of an electrical outlet with GFI (Ground Fault Circuit Interrupter). Excavate the pool and check that the edges are all level using a hose level on large  pools or a straight 2x4x8 laid across the pool and level placed on top of the 2x4 to level a small  pool.  Fill in any low spots to prevent the water form washing out.  The sides should slant inward at an angle of 15 to 20 degrees.  Remove sharp rocks from the hole and put down a layer of sand followed by a felt type under liner.  To calculate the size of the liner determine the length, width and depth of the pool.  Double the depth and add  this number to the length and width.  Drape a flexible PVC liner ( minimum 15 mm) loosely and evenly over the hole.  Fold or pleat the liner to achieve the desired shape.  Fill the pool slowly smoothing the liner so it fits snugly. Anchor the edge of the liner with rocks.  The rocks should be thick  and deep enough to allow the liner to go under and up behind the rocks such that the finished water level is above the showing liner and below the top of the finish rock.  This gives a more natural and professional look. Consider leaving a sloped area to allow animals that fall into the pool access to crawl out. It is also a good idea to install a drainage pit near the pool in the event of a heavy rain to allow the overflow from the pool to be directed to a safe location rather than rising water level to wash out the edge of your new pool.    OTHER ELEMENTS: Streams add a number of elements to the garden atmosphere.  It will add music and light while connecting one part of the garden to another visually and physically. Waterfalls are another popular garden feature.  When constructing waterfalls it is important to keep its size in scale. It should not overpower other features in the garden while remaining natural looking. Fountains, Water spouts and Bubbler Stones:   water moving through any of these features are exciting elements and are suitable for any type of pool providing a soft splashing noise.   If floating plants and small aquatic animals are in the pool, then the water disturbing fountains and such should not run continuously.   ADDING WATER LILIES:    After filling your pool, wait one week before adding plants and two weeks before adding fish.  This allows time for the pool and water to stabilize. Lilies require plenty of sun, rich soil and quiet, shallow water.  They are planted in heavy clay loam - do not add manure or peat to the mixture.  They are organic free.  The plants are potted up and sunk to the appropriate depth (8 inches).  They should be fertilized each spring and may be dug and divided after two to three years.    SUGGESTIONS: * Do not change the water in the pool. * Be sure you have sufficient plants for a balanced pool.   Oxygenating plants provide oxygen and help to absorb excess, dissolved nutrients.  Lilies provide shade and use up nutrients as well. * Oxygenating plants grow under water.  Set them at the pool bottom.  Choices include:    - Elodea   - Cabomba   - Sagittaria natans.   - Hornwort *   Hardy shallow water and bog plants.  These are planted at the pond edge - either at water level or up to 6 inches below water level.  Choices include:    - Arrowhead (2 inches below water level).   - Blue water iris (as above)    - Cattail (as above)   - Marsh Marigold (plant at water level) *   With fish, use only PVC flexible liners.  Plastic liner can leach toxic chemicals that will kill plants and fish. * Lilies may need a depth of 36 inches to overwinter safely.  They should have from 6 - 12 inches of water over the soil or crown of the plant - the best depth is 8 inches - during the growing season.     Vol. 97 no. 10
© Murray's Garden and Horticultural Services Last updated: March 2, 2008