Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: FRIDAY, March 11, 1994 TAG: 9403140126
SECTION: LAWN & GARDEN PAGE: 10 EDITION: METRO
SOURCE: BETSY BIESENBACH STAFF WRITER
DATELINE: LENGTH: Long
"The demand for water gardens is growing," said Norman Tharpe, owner of Tharpe Landscaping Company. "People really want them."
"It's a fascination with the water," agreed Larry Booth, landscape foreman for Belle Aire Garden Shoppe in Roanoke. "It ties the different parts of the garden together," because it combines the two most basic elements of gardening: water and plants, he said.
There are several different aspects to consider when constructing a water garden. First, it's important to check local guidelines regulating outdoor pools. Many places, especially cities, require that the pond be fenced in if it is more than 2 feet deep. It's also a good idea to check with utility companies before you start to dig.
Perhaps the most important component of the water garden is the material used to line the pond. For many years, just about the only way to create a firm, nonporous surface was to put down a layer of compacted clay.
Many landscapers have used concrete, but in severe weather conditions, it can heave, crack or buckle. The concrete also contains lime, and if it's not cured properly, it can leach into the water and harm fish and plant life.
Mail-order companies and garden shops often sell preformed fiberglass liners that come in a variety of natural looking shapes. The purchaser then digs a hole to conform to the shell.
Flexible rubberized and PVC liners are becoming more and more popular, Tharpe said. He offers a special rubberized liner that is 45 to 65 millimeters thick, depending on the customer's preference. It comes with a 35-year guarantee, and is so strong that Tharpe once dug into one with a garden spade and didn't damage it. In fact, the liner is so specialized that Tharpe won't sell it to anyone else because he wouldn't be able to keep it in stock for his clients.
Belle Aire Garden Shoppe offers a PVC liner that is 32 millimeters thick. The liner material comes in large rolls, and is flexible enough to conform to a hole of almost any size, shape or depth. The liners are usually set in a bed of sand or foam.
The type of material used to finish the edge of the pond is important, too. Not only will it conceal the edges of the liner, it serves to weigh down the rubberized materials.
Most landscapers will set rocks or bricks in mortar around the edges. Booth uses wet newspaper to create an underlining for the edge during construction, and sometimes lines the outer edge of a fiberglass shell with moss.
Many gardeners like the effect of a waterfall cascading down from one pool to another. When building a waterfall, placement of the rocks is crucial to ensure a natural-looking flow. If not done correctly, the water will flow around the rocks and go everywhere except where it is supposed to. In fact, Tharpe said he once spent three hours placing just one rock.
The pump is a very important element of the water garden. Usually, the pond is filled once and then topped off during the summer months to compensate for evaporation. Depending on the size of the pond and the kind of pump, the water can be recirculated every few hours. The pumps are electric and are supplied by a connection from the house.
The pump is generally turned off during the winter, and the water is allowed to freeze. The freeze line for this area is two feet, Tharpe said, and fish can hibernate safely under the ice as long as they're not disturbed.
But a water garden is more than a just a decoration. When planned right, it is a self-contained ecosystem.
Soon after the pond is filled, Tharpe said, algae move in and begin to grow. If fish are introduced, they will eat the algae and keep it under control. Most people choose goldfish or Koi, a large, friendly breed of carp that resemble goldfish.
Plants are necessary to keep the fish cool and to provide them with hiding places from backyard predators, such as dogs, cats and raccoons.
There are three varieties of plants used in water gardening. The first are set in containers at the bottom of the pool. Completely submerged, they produce oxygen that is released into the water. Other plants, such as water lilies, have their roots submerged while the foliage floats on the surface. They are planted in pots placed on shelves or blocks below the surface of the water. Marginal plants are set on the highest shelves or right next to the edge of the pond. They give the water garden a more natural look.
Booth said some gardeners get worried when the water clouds up occasionally, but like a natural pond, he said, "the water isn't always clear."
If the water garden is set up properly, it needs very little maintenance. In the spring, owners should remove leaves and other debris from the water. It's also a good idea to roll up the pants legs and wade on in every once in a while to prune and otherwise care for the plants.
Even the fish should be able to find enough food on their own, but many owners feed them anyway, to enjoy watching them come to the surface.
by CNB