How to Create a Water Garden, a Soothing Backyard Feature for Aquatic Plants and Fish

A container water garden allows you to bring new plants and wildlife into your backyard in a way that traditional flower and vegetable gardens cannot. The small ecosystems provide a habitat for aquatic plants, like water lilies and water hyacinths, and can even sustain small goldfish and mosquitofish. Additionally, they will fill your landscape with the tranquil sound of running water and color from the wildlife that is attracted to them. Ready to create your own? Here, we explain how to make a container water garden, from choosing plants to adding fish.

What Is a Water Garden?

Water gardens can occur naturally or be constructed in a container, in-ground pond, or a bog and are incorporated into garden settings. The miniature, self-contained aquatic ecosystems hold water with true aquatic plants and plants that tolerate being grown in water. “They can also play a crucial role in supporting wildlife by providing a natural water source for birds and a habitat for various aquatic creatures,” says Mary Phillips, head of native plant habitat strategy and certification programs at the National Wildlife Federation.

Benefits of a Water Garden

There are many benefits of incorporating a water garden into your landscape, ranging from ecological benefits to aesthetic ones. 

They Add Color to the Garden

Water gardens bring unparalleled beauty into the garden. “Extravagant floral displays offer opportunities for enjoyment both during the day and night with the incorporation of night-blooming plants,” says Tim Jennings, horticultural specialty grower at Longwood Gardens. ”The unique colors, forms, and textures of the plants often inspire creativity and artistry—think Claude Monet’s famous paintings.” Additionally, the sound of the water adds another dimension of tranquility. 

They Improve Biodiversity

This garden feature helps increase the biodiversity of wildlife in your landscape, says Linda Langelo, horticulture specialist at Colorado State University. The water provides a place for birds and other wildlife to grab a drink of water and can become a home for fish, frogs, and insects. 

They Help Control Mosquitoes 

When cared for properly, water gardens can even help control your backyard’s mosquito population. “While stagnant water can attract mosquitoes, a well-maintained water garden with moving water and certain fish species can help control mosquito larvae,” says Phillips. 

Best Containers for a Water Garden

Water gardens can be created in a range of containers, including a metal bucket, resin tub, whiskey barrel, bathtub, or a concrete trough, so long as they’re non-porous. “Larger containers are the best type because you need space and depth to create a viable habitat for plant roots and fish,” says Langelo. Note: if you do use a wood or metal container, make sure you add a liner as wood can hold bacteria and metal can kill the fish. 

Best Plants for a Water Garden

A healthy water garden will resemble a natural pond, with plenty of native plants, some debris on the bottom, and a log or branch floating on the surface, says Phillips. 

Floating Plants

Floating plants that dangle roots into the water provide a quick cover for the water's surface and help cool its temperatures during warmer water. “A word of caution, many states now have restrictions on which plants you can safely grow, some are considered invasive and care must be made to keep them from escaping into natural bodies of water,” says Jennings. 

Examples: Duckweed, water lettuce, water lilies, lotuses, water hyacinth, and spatterdock.

Bog Plants

Also known as marginal plants, you will typically find bog plants growing on the margins of creeks and streams. “They prefer to grow in saturated soils and in water up to several inches deep, depending on the type,” says Jennings. 

Examples: Water iris, rose pogonia, lady’s tresses, sundews, and pitcher plants.

Oxygenators 

Oxygenators are submerged at the bottom of the water garden. “They keep algae growth under control, provide shelter for fish, and provide oxygen,” says Langelo. 

Examples: Hornwort, eelgrass, anacharis, cabomba, and feather grass. 

How to Make a Water Garden

Now that you know what you’re going to put in your water garden, you can begin creating it. 

Choose a Location

Select a location where your water garden will receive about six to eight hours of direct sun (aquatic plants are sun lovers!) with some shade during the hottest part of the day. “This will help control algae and the temperature of the water,” says Phillips. “Cooler water holds more oxygen and will be more comfortable for the plants and creatures that inhabit the pond.” 

Avoid placing your water garden in a low-lying area that may direct unwanted run-off from rain and irrigation into your pond, says Jennings. Also, consider ​the location of large trees, which cast shade and can become a problem in the fall when leaves drop.

Prepare Your Container 

Place your container in the location you’ve chosen, then begin preparing it for your plants. “If your container is wood or metal, you should line the container,” says Langelo. “Galvanized metal will kill the fish. Water is a solvent, and if water is constantly touching the galvanized metal directly, the container will rust and break down over time.” Generally, plastic stock tanks don’t need linings. 

After adding your lining, consider laying down rocks on the bottom of the container. “Rock provides a medium to which the roots can attach themselves,” says Phillips. Rock also provides a place for bacteria to colonize, which is ideal if you are adding fish to the water garden.

Add Bog Plants

When adding bog plants keep them in their plastic pots and place gravel over the soil in the container to keep them in place. "Once they are arranged the way you want them, then add water to the container," says Langelo.

Fill the Container With Water

It's best to fill your water garden with rain water or water from a nearby natural pond. "Water from your tap that has a softener in it is not recommended for use to fill a water garden because it has a high concentration of salt," says Langelo. If you do need to use water from the tap, consider using a de-chlorinator. "Keep the water level close to the rim or provide a branch to enable small birds to drink from the water feature," says Phillips.

Add a Water Pump

Before adding additional plants, consider installing a water pump to keep water circulating. This feature creates a soothing sound that adds ambience your landscape, and also prevents mosquito larvae from hatching.

Add Floating Plants

Add floating plants like water hyacinths and water lilies to your garden. "These plants don’t need soil, their roots come in direct contact with the water, and they draw their nutrients from the water," says Langelo. "They help provide additional shade and hiding places for the fish."

Add Fish

Once your water garden is established, you can introduce small goldfish and mosquitofish. "It is recommended to wait a couple of weeks before adding the fish to allow the good bacteria time to establish," says Langelo. When the water garden is covered by shade, take the bag of fish and submerge it for about 15 minutes before releasing the fish. Feed them regularly while allowing the algae to build as a food source, she says.

How to Care for a Water Garden

Unlike some gardens that require regular watering and fertilizing, water gardens are relatively low maintenance.

• Drain and clean the water garden when 2 inches of decomposed matter builds up on the bottom, says Phillips.
• Use fertilizer sparingly, as water and soil will give plants the necessary nutrients.
• Use mosquito dunks regularly to help with mosquito control, says Phillips. They can be found at your local garden center and contain a strain of bacteria that is toxic to mosquitoes but safe for wildlife and people. 
• Remove any flowers, leaves, or foliage before they start to decompose, says Langelo.
• Add a float to the water to maintain proper water levels for the water garden plants.