Water Gardening

©Copyright 1993-2002 The L. W. Ramsey Agency 1-800-473-0157

Bringing the Best of Nature Home

One of the most popular and exciting new trends in gardening today is water gardening. You don’t need either an estate or a gardener to have one. Any water-tight container, such as a half-barrel, can allow you to grow water lilies and other aquatic plants.

There was a time when “They have a pool’ usually meant a swimming pool, a sure sign of great wealth and lavish spending. The time has come when having a pool can well mean you can have a clear reflecting pool, a fishpond, or water garden as a focal point in a lovely yard. With the improvements in liners and preformed fiberglass, such an intriguing feature is now within the means of almost everyone with a garden. Most take much less work and room than a swimming pool and appeals to a wider range of people.

Trickling water sets a mood of liveliness, movement, and enchantment; standing water of peace and tranquility. Both enhance the feeling of privacy and security in a world of your own that reflects the changing seasons and moving clouds overhead.

Even the most unhandy person can now install a pool in two weekends and maintain it with much less work and expense than most people expect, little more than needed for a standard flower border. An evening’s study of this booklet, followed by the help of your distributor, will get you started, even if you are completely unfamiliar with the subject. You’ll enjoy every aspect of learning as you go. Tub Gardens Top of Page
These miniature water gardens are available even for apartment dwellers on a patio. They bring beauty and uniqueness to any setting. Children love them and can easily plant and care for their very own.

You can use large ceramic planters, old wash tubs, bathtubs or kettles, or specially purchased containers. Bury these or not, depending on their aesthetic value. Old barrels make fine tub gardens, but they may contain bacteria harmful to plants and fish even after charring. To overcome this, line such tubs with a sheet of pool liner and secure the edges.

To plant a tub garden

  • When using city water use a de-chlorinating agent according to label directions. Chlorine is deadly to plants & fish.
  • Fill the tub slowly with water from a pencil-thin flow from the hose into the bottom of the tub
  • Plant water plants in 10 inch pots and position, one at a time. Use blocks, bricks, or overturned pots to bring pots to the proper level for each plant. Include some bog plants like cattails or arrowhead that will give standing leaves above the water. Put a layer of rocks, gravel, or sand over the top surface of the pot to keep the soil from washing out.
  • Place a lily in the center for a focal point.

  • The larger the tub the less water temperatures will fluctuate. Some tubs will be large enough for gold fish but not for Koi. In small tubs you should add Mosquito Fish (Gambusia) or Guppies to eat mosquito larvae and some water snails to keep the water and plants clean.
  • Watch carefully. A tub should achieve balance in about 60 days, usually without chemicals. Use an algae inhibitor only if needed.

    Winter Care Top of Page
    Lest you think cold winters eliminate water gardens, take heart. With minimal care, your plants and fish can survive in the pond, or you can move them indoors until spring.

    In mild climates or with added heat from a floating de-Icer, fish will live under a foot of ice as long as an air hole is kept open to let oxygen in and noxious gases out. Don’t make holes by smashing the surface or the concussion could damage or kill the fish.

    Putting a few logs in the water will absorb the pressure of the ice so the concrete or liner will not crack.

Water Scarcity Top of Page
If you are concerned about saving water, good. But this also does not rule out a water garden. Here are some proven facts.

  • A pool takes less water to maintain than does the lawn it displaces.
  • With today’s new pond construction materials and methods, leakage is completely eliminated. Pond water, unlike water put on a garden or lawn, does not seep away.
  • To cut evaporation, have straight up and down rather than sloping sides on your pool.
  • Use water fountains or falls only when you are outside to enjoy them or put them on a timer.
  • The presence of a pool offers psychological benefits, a feeling of lushness and added serenity.

Waterfalls or FountainsTop of Page
It is possible to buy fountains that are complete units and require only electricity, no pool at all. A simple set up, water running from a pipe back into a rain barrel can add the enchanting sound of trickling water to a garden.

To install a fountain in any water-holding container requires only a submersible pump, a screen for the inlet, a length of pipe to reach just above the water surface, and the fountainhead. Various heads will give different patterns. The aeration of the water also helps to keep it clean.

Waterfalls can be a trickle of water over stones or a cascading wall. They are usually constructed in conjunction with a pool that should be four times the size of the waterfall. Often the dirt from digging the pond, arranged with rocks, makes for a natural look as the pond backdrop; or cover existing walls, large drums, or cement blocks for a backdrop. A liner all in one piece for both pool and waterfall is best. Use either cement or a pool liner. Arrange rocks carefully so they do not tear or puncture and do not trim the liner until the waterfall runs for several days to allow for any changes as the pool settles.

A drip stone overhanging the edge of the pool with airspace beneath and some hollow space behind the falling water will accentuate the sound of the falls.

Run flexible tubing from the pool to the top of the waterfall. If you know the height of the fall, the length for the tubing, and the volume of water in the pool, your dealer can guide you in the choice of a pump. In fact, dealers and landscapers who specialize in these products will be glad to help you choose all the components needed and make sure you understand how to use them for maximum enjoyment.

Install the pump, fill the pond with water and take PH and chlorine readings. Wait a week while water circulates and this should eliminate problems. Do this before adding plants or fish.

It is certainly possible to have fish, plants, and a waterfall as well if a pool is properly designed.

Put Safety First Top of Page
Check with local building and electrical codes. For pumps, filters, and underwater lights, most codes require a weather-proof receptacle within 6 feet of the pump and 18 inches above the ground, protected by a ground fault circuit interrupter (GFCI) that will shut down at once if a potentially dangerous malfunction should occur. Most underground wiring requires an underground feeder (UF), rigid conduit, or a combination of conduit above ground, UF below. Codes also say how deep these must be buried, and it does not make sense to take any chances with such a potentially dangerous combination as electricity and water.

Other Additions Top of Page
Electricity may not be needed at all in a natural pool with plants and fish. However, a reflecting pool with only water will need a filter, either mechanical or biological, and pump to keep the water clear and some prefer to use these in fish ponds as well.
You may also want to install underwater lights. If not, there are lovely floating candles for use on ponds or on swimming pools on those special occasions when you are entertaining at night.

Most pools do not need a drain. Just empty by bucket or syphon on the rare occasions when needed; at the most once a year for small pools in cold climates where you start anew each spring. Use this water for watering other plants as it is rich in nutrients.

Design is Important Top of Page
Place your water garden where it will be in harmony and scale with the rest of the landscape and where you can enjoy it most from indoors looking out or from outdoor living areas.

The site should have as much sun as possible for the lilies and other aquatic plants. They need a minimum of 5 to 6 hours of full sunlight a day for best bloom.
Also choose a place away from deciduous trees and shrubs. The leaves that make such good mulch in a garden make trouble in a pond as they produce noxious gases that could harm fish. Take note of young trees that are going to grow much larger and wider and bear that in mind.

Select a level location. Avoid low lying spots where water may accumulate in heavy rains, flood your pool, destroy your plantings, and wash away your fish. Even smaller amounts of water can wash in weed killer, lawn fertilizer,or other harmful chemicals or simply add too much water at once and disturb the balance of the pool’s ecology. For goldfish, a pool should be at least as large as a bathtub. An area of 50 square feet or more is best, For most goldfish, 1 1/2 to 2 feet is deep enough. Japanese Koi need 3 feet of depth. Smaller pools need more careful balancing. Build the largest pool your landscape and your budget can accommodate. The more water, the less it is subject to environmental upset, and the more plants and fish you can have. But remember it is not the size but too much sun and feed and not enough plants that lead to algae problems.

Keep in mind electrical possibilities in case you later decide to add a pump, fountain, or lighting fixtures.

Choosing a Pool LinerTop of Page
A pond or pool is essentially a hole in the ground filled with water. To keep this water in place, you have a choice of liners.

1. EPDM is a synthetic rubber membrane and is .045 mil. Easily installed, it is the most flexible of all liners and has the longest life of any membranes used for pond liners. It is UV resistant, fish friendly and extremely user friendly.

2. PVC (poly vinyl chloride) sheeting has great strength with enough elasticity to stretch with earth movements or ice pressure. These liners are black, 20 mil. thick, and comparable in durability and length of life to concrete. Should a sharp object puncture the liner, a patching kit will handle the repair easily and effectively. There can be slight shrinkage, up to 6 inches, so don’t cut off edges too soon
3. HDPE (high density polyethylene) is a new material, also black, 45 mil.; thicker and stronger. It’s more resistant to UV rays. Free of Toxins and often guaranteed for 10 years.

4. Cement is usually applied over tie rods or a wire frame. Apply wet cement to the wire 3-4 inches thick. Work quickly and dampen as needed. Then cover the pond with polyethylene to slow the curing process and keep rain water out. Wait a week for curing. Then apply the coping or lip with the help of a level. Fill and let stand at least a day, then drain. Scour concrete, rinse well, and seal the surface with pool paint.

5. Preformed pools are usually made with plastic, fiberglass, or a combination. You can let sturdy ones stand partly above ground or use them in greenhouses or indoors, anyplace where the floor will bear the weight. Select the shape that best fits your plans, again the larger the better.

Building the Pool Top of Page

  • First outline your pool on the ground with a hose or rope. Allow the liner to warm in the sun so it will be more flexible.
  • Dig the excavation at least 18 inches deep or 6 inches wider and 3 inches deeper than a preformed liner. Let the floor slope 2%. Remove all sharp objects. Add 2 to 3 inches of sand in the bottom and padding such as an old carpet or a thick layer of newspapers to cushion the sidewalls. Be sure the rim is level.
  • Then lower in the preformed pool or drape the liner loosely over the area with an even overlap. Weight the drape around the edges. Slowly fill pool half way and let the water mold it to the ground. For sharp angles, you may need to fold the liner into the corners. Check the rim level again. Fill to the brim. Check rim level. Then fill the gaps around the preformed pool with soil or sand. See above for cement construction. Hide the drape edges when you are sure everything is set. It is best not to do this until you have plants in place.
  • All pools need a rim of 1-3 inches to keep out groundwater. These rocks, bricks, or paving stones will hide the edges of the liner and add the finishing touch.

Balancing Top of Page
Allow the lined pool to settle or cure a concrete pool for a week before adding plants first and then fish. A pool will bring no more, perhaps fewer mosquitoes if you maintain a good ecological balance.

It may take 2 weeks to 2 months for your pool to reach a natural balance where the fish, snails, oxygenating plants, and lilies will usually keep the water clear and clean and the algae in control. In the meantime, don’t be alarmed if your pool turns murky. There will be some algae wherever light and water exist together. A few will turn the water slightly green and this is alright. Too many will make it pea soup.

To prevent too much algae buildup add needed plants and give them time to become established. Keep decomposing material to a minimum. Skim falling leaves. Prune old foliage. Use chemicals only as a last resort and select them carefully or they can also kill plants and fish. Once balanced, ponds can reamain balanced for years with proper maintenance. Whatever you do, DON’T DRAIN THE POOL. This will just start the balancing process all over. Also, do not spend more than one hour per one thousand gallons of water working, with hands in the pond, once established, or you will disrupt the balance.

Though pools differ with depth, temperature, and sunlight, a good general rule to remember is:
For every square yard of surface, have
·Two bunches of
oxygenating grasses
·One medium to large
water lily
·Twelve water snails
·Two fish, 4-5 inches
Oxygenating Plants Top of Page
These grow under water and produce oxygen in the process of photosynthesis. You can often see bubbles of oxygen arising from these plants. If you have enough of them, they make it difficult for algae to thrive by consuming most of the carbon dioxide from the fish waste and decaying plant matter. They also make a bed for the eggs and baby fish.

Plant two bunches of oxygenating grasses per container. If the pond is green when you put them in, elevate the pots so they get enough sunlight. Gradually lower them to the bottom as the pond clears. Should the fish eat your plants, put six-inch cones of one-inch mesh wire over each plant. This will save enough of the plant so it won’t hurt if the fish eat what grows through the mesh.

Water Snails Top of Page
These are good snails who eat the algae off your plants and pots. They lay eggs that look like white jelly on the underside of lily leaves, so be careful not to trim these away. Water snails will not leave the pond or eat any decorative plants. When you get them, float the bag for twenty minutes before releasing to equalize the temperatures, just as you do for fish. Replace them, should they disappear, until the pond balances.

Water Lilies Top of Page
Water lilies are very important as their leaves provide surface coverage, thus cutting down the loss of oxygen and keeping the pond from breathing too fast. Besides being the loveliest and showiest of water plants, their leaves provide needed underwater shade and keep the water cooler. By summer a pond should have 50 percent coverage.

These exquisite flowers come in many colors and sizes. They do best with roots in containers on the pond floor or elevated to the proper depth. Most are easy to grow, once established and will bloom freely from spring until late fall. Do not be upset if the first flowers are not the color you expected. Color varies with conditions and will intensify as plants become established and the pool reaches balance.

You can start water lilies from seeds, but most people start with plants. The hardy lilies multiply quickly with spreading tubers.

In warmer climates or where you can move lilies indoors over winter, you’ll also want some of the tropical lilies, which have larger flowers that come in a wider range of colors. Some are deliciously fragrant. Some bloom by day, others only at night.

Edible Water Plants Top of Page
Edibles like lotus, water chestnuts, and watercress can grow in the pool, and celery, cranberries, natal plums, bananas, citrus, clump bamboo, sorrel, and many herbs do well on the moist banks. Lotus can take over, so harvest the tubers often enough to keep them in control and eat or can, freeze, or dry them.

Planting Top of Page
Plant anytime after the weather warms up in the spring and at least a week after you fill your pool. You can plant in bottom mud, but containers allow flexibility in depth and position and make cleaning and care easier. Use a mix of garden loam and aquatic plant fertilizer. Do not use swamp muck, compost, peat moss,
or dry manure.

Submerge oxygenating plants first. Fill several 5-inch pots or shallow containers with soil with an inch of sand on top. Root several oxygenators per pot by pushing them a third of the way into the soil.

Put one water lily per pot, the size recommended by your nurseryman. Hardy lilies should be planted at an angle against the pot side. Store indoors in harsh climates over winter.

Plant tropical water lilies when the nights grow warm. Set tubers in the center of the pot with the crown at the soil line. Sink the pot with 6 to 8 inches between the soil and the water surface. You can’t treat these as annuals and order new roots each year.

Fish and Other Water LifeTop of Page
Plants and fish work together to keep the water clear. Add one fish per 2 sq. ft. of pond surface. You can choose from many colorful goldfish such as calicoes, comets, blackmoors, and fantails. If your pool is large and deep enough, you can add Japanese Koi.

Do not let the bags in which fish arrive get hot in the sun. Float bags in the pond for 30 minutes before setting the fish free. This will equalize the temperatures.
Feed pet store food, as directed, every one to three days. You can easily train fish to come to a signal and eat from your hand. Remove any food left after 5 to 10 minutes. Give extra protein food in the fall and none in winter, a natural resting period for the fish. Do not overfeed.

Welcome any frogs or toads that come. You can also buy these. With the fish, they help control insects and algae growth. Turtles can eat plants and fish, so are best excluded.

Maintenance Top of Page
Whenever you are near your water garden with a hose, daily if possible, spray plants to wash any insects into the pool where your fish will take care of them. This will also add a little water to make up for evaporation. Never add large amounts at once or you will disturb the balance. Remove dead foliage, skim off debris, and treat for algae only as needed. Closely observe plants, fish, and liner often simply to enjoy the sight, but also to check for any problems. If you close down your pool for the winter, you’ll want to clean, refill, and balance it again every spring. Otherwise, you need only empty and clean it every several years in the spring.

As your plants multiply, you will need to give some away or sell them so you can try new ones. The same may be necessary with the fish.

Bog or Marginal PlantsTop of Page
These plants are ideal for the edges of a pool, the banks of a natural brook, or any spot where the soil is constantly moist throughout the growing season. A pool will not necessarily have a damp edge, so you may want to extend the liner to include a shelf 8 inches deep. See the next section for situations where bog plants make a garden of themselves.


Cardinal flower
Closed gentian
Fringed gentian
Forget-me-not, water
Horse tail
Iris, bulbous (not bearded)
Marsh marigold
Pickrel weed
Pitcher plant
Royal fern
Sweet flag
Wake robin




Floating plants like water lettuce, floating heart, or water hyacinth need no soil. These do provide oxygen, but are not a substitute for oxygenating plants. They remove excess nutrients better than other plants and provide hiding places for eggs and shelter for fish. When these spread too far, just scoop out the excess.

Bog GardensTop of Page
On land where there is a natural bog area, where the water does not stand in pools, but the soil is constantly saturated, another unique garden opportunity awaits. Instead of going to the expense of draining the bog, plant some of the plants that thrive under those very conditions. Clear the area of other plants, add compost to the soil, and plant with a naturalistic design.

For people who do not have a bog, it is possible to create the required condition: a continuous supply of water and a soil capable of retaining it. Use a soaker hose or low flow irrigation system buried about 2 inches below the soil surface. Mix sand and peat moss in equal portions and add other humus in generous quantities to a depth of 18 inches. Use a sunken tub or wading pool for most efficient control or simply remove and replace other soil in a low-lying spot.

Once planted, the only care required of a bog garden is occasional removal of unwanted plants that may creep in.

Getting StartedTop of Page

  • Pick the location – Sunlight – Few falling leaves – Focal point
  • Plan the design -Tub – Pool Liner -Edging rock or brick
  • Plants – Oxygenators – Lilies – Bog plants
  • Containers
  • Fertilizer
  • Fish
  • Snails
  • Algae control chemicals
  • Pump for waterfall
  • Fountainhead
  • Filter where needed

Some facts may vary by region. Please check with your local lawn and garden dealer if concerned about possible variations.