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How to Grow a Specialty Garden


Maintaining a Water Garden
Moving water is not required in a water garden -- aquatic plants, for example, grow best in still water -- but a waterfall or fountain adds several advantages. Moving water is better aerated than still water so fish do better. A filter can easily be added to any pump, making water clearer. But the main reason for including a pump in your water garden is aesthetic: People enjoy the sound and sight of moving water.

Care should be taken to avoid creating strong currents or excessive splashing near aquatic plants or they can be damaged. Fountains especially are not conducive to plant life, as their spray can reach considerable distances under strong winds. Waterfalls can usually be separated from water lilies and other plants by placing the cascade at one end of the pool and installing a few well-placed rocks to diffuse the current.

Choose the form of moving water that best corresponds to your pool. Fountains and other pool ornaments are best for formal pools. Waterfalls cascading over rocks work well for irregular pools in a more natural setting. And simple underwater filter systems suit any kind of pool.

There is no lack of choices among fountains: cones, sprays, jets, bubble effects, or pretty much whatever you want. Pipe heads can also be fitted to ornamental statues, ceramic jars, or bamboo pipes. When installing a fountain, make sure the height of the spray is not more than half the diameter of the pond; otherwise much of the water will end up being sprayed out of the pool during windy periods.

If your yard has a natural slope, consider installing a waterfall: It will help integrate your water garden into the rest of the landscape. Waterfalls can also be used in flat areas, but care should be taken that the resulting raised section doesn't stick out like a sore thumb. Place tall plants or a fence behind the waterfall to ease this potential problem. The combination of rock gardens and waterfalls is a natural one since the waterfall is set off by rocks anyway and rock garden plants, generally low-growing, won't block the view of the resulting stream.

Prefabricated waterfall units are readily available and easily installed. They may consist of an entirely preformed section with several tiers, or they may be individual catch basins designed to be placed so that each one slightly overhangs the previous one. It is also easy to make your own waterfall using a section or sections of flexible liner.


There is a wide variety of pumps available for water gardens. The pump should be chosen according to the quantity of water to be moved, the distance the water has to cover, and the height the water is to be pushed. For example, it requires much more power to pump a fast-moving stream of water five feet up and ten feet from the pool for an extensive waterfall than to simply filter the water in a pond. Pumps generally come with charts detailing their capacity. Ask the supplier to help you choose if you have any doubts.


Always select a pump somewhat stronger than your needs, just in case. The pump should never have a rate of flow per hour greater than the capacity of the pond, but it should be able to circulate nearly half the pool's water per hour. To calculate the approximate volume of your pool, multiply its length by its width by its depth (in inches). This gives the number of cubic inches. Divide this by 231 to obtain the number of gallons. For example, a pool 10 feet (120 inches) by 6 feet (72 inches) by 18 inches deep would have a volume of 155,520 cubic inches, or 673 gallons. A pump rated at 300 gallons per hour would be adequate.

The pump in this water garden keeps water flowing.
©2006 Publications International, Ltd.
The pump in this water garden keeps water flowing.

Water filters are not necessary for a healthy pond, but they do help keep the water clear and the pool free of debris. Mechanical filters are still the most popular and need only regular cleaning or replacement of the filter. Biological filters take up more space but need little upkeep.

Choosing a Pump

The most commonly used pump is a submersible pump, which can be placed out of sight under water. For small ponds, a 24-volt pump may be sufficient. Larger ones using a regular 110-volt house current are the norm for larger pools. If there is no electrical outlet near the pond, have one installed by an electrician. Any underground wiring should be placed at least 18 inches deep and run through PVC piping to avoid accidental breakage. A ground fault circuit interrupter is recommended in all cases.

Maintaining a Water Garden

Keeping a water garden attractive and healthy is surprisingly easy.
  • Occasionally remove plants to prune away dead or dying leaves. While you're at it, insert fertilizer tablets, about one per five quarts, into their containers.

  • Remove any dead leaves and other organic material that has accumulated on the pool bottom.

  • An occasional spray with a hose will knock any aphids that have developed on plant leaves into the water where fish will eat them.

  • Clean the filter occasionally according to the manufacturer's instructions.

  • Add water as necessary to maintain the proper water level.
Winter Care

Winter care is also quite simple. In most climates, hardy plants can be left as they are. In cold climates, though, sink even hardy plants in the deepest part of the pond (three feet or more) to prevent freezing. In extremely cold areas, pools will freeze to the bottom. Tropical plants must be brought indoors for the winter in all but the warmest climates.

It is normal for the water in a garden to turn soupy green upon occasion, especially early in the spring or when nutrient-rich fresh water is added, which can cause a rapid increase in the algae population called a "bloom." If the pool is properly balanced, with plenty of oxygenating plants to reduce the carbon dioxide level, abundant floating or emergent plants to absorb nutrients and shade algae out, fish and scavengers to consume the algae, and some water circulation, algae blooms should be of short duration. But don't expect water in a garden pool to be perfectly clear. That isn't any healthier for fish and plants than green water.


Whether your preference is for a water garden, rose garden, rock garden, or organic garden, a specialty garden can be the perfect piece for your landscape.

2006 Publications International, Ltd.

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