If one of your goals in designing your garden is to attract desirable wildlife that is environmentally beneficial to your yard and neighbourhood, this should interest you: a water feature is the most beneficial addition to your yard and garden that you can possibly make. A full-blown pond or a half-barrel-sized container full of water and plants will do more to create biodiversity than a swath of petunias or a row of gorgeous cedars, neatly trimmed and manicured. Think of it this way: How long can you survive without water? Ditto the wildlife that would love to live at your place. Sure, the songbirds love your bird feeder and may occasionally splash in your bird bath, but there is more to attracting good things to your garden. Many species make use of small watering holes. Frogs, toads, salamanders and dragonflies can thrive in a surprisingly small body of water.
Here are some tips to help you develop your own plan for a water feature that is environmentally beneficial.
• Water should be at least 80 cm (31.5 inches) deep. If you wish to overwinter fish and frogs, it should be at least a metre and a half deep in the Toronto area; deeper if you live up north, where winter temperatures fall further.
• A natural-bottom pond will attract a wider range of wildlife in the early years than a plastic lined pond will, but over time a pond liner can accumulate enough organic matter at its base that it, too, will attract a variety of wildlife.
• Water that moves, like a fountain or waterfall, will eliminate the potential for mosquito breeding, is easier to keep clear and attracts more wildlife.
• Your pond should be located in a partially shaded place, if possible. No more than four hours of sunlight a day is ideal; more will encourage algae growth.
• To attract wildlife, your pond should have sloping sides to make it easy for animals to enter and exit (but not too gradual a slope or raccoons will scoop up your fish).
• A variety of depths in your pond will allow a greater diversity of critters making their home there. Birds and tadpoles migrate to the shallow areas, while frogs, toads, newts, salamanders and turtles like deeper options.
• Perennials should be planted around the perimeter of your pond. As they mature over the years, they will provide protection for the many amphibians that move around the water’s edge.
• Annual floating plants should be used in the early years of your pond to provide shade and protection for pond life. As the plants and trees mature around your pond (and you get closer to achieving the required shade on the surface of your pond), you can eliminate the use of floating annuals like duck weed and floating hyacinths.
• If you fill your pond with chlorinated (city) water, it should sit for at least a week before you place fish in it. When you refill your pond, it is best to use rain water from a rain barrel.
• Wildlife that make your pond its home should not be moved and plants or wildlife from the wild should not be imported to your pond. The critters will find it as sure as lions and zebras find the watering hole in the Serengeti Plain, and plants are best acquired from a reliable retailer.
• Water plants can help keep the water clean and oxygenated, and others will attract pollinators, especially the plants that flower throughout the summer.
• The water depth must be considered carefully for plant placement. Marginal plants perform best at the water’s edge, while native lilies enjoy a depth of about 60 to 80 cm (24 to 31 inches).
• Native plants (nursery grown) are more likely to attract native critters.
Our favourite aquatic plants
A hardy plant for shallow water. Best planted at the edge of your water garden. Cattails have tall foliage. Famously known for their brown catkins in early autumn. Many varieties are available ranging in size and colour.
A great choice for ponds or bog gardens. Irises grow well in full sun or partial shade. They are available in a variety of colours. Our favourite is blue water iris. They bloom in spring for a spectacular show. The foliage is tall and very showy through the summer months.
We prefer hardy water lilies over the tropical form. Hardy water lilies can be left in the water garden all year. They require a minimum of six hours of sunshine each day. The blooms will appear on the water surface. Hardy water lilies are available in white, pink, yellow and red. You will discover a whole new world in your backyard if you are successful in attracting beneficial wildlife to your pond or water feature. Note that dragonflies eat insects, including mosquitoes. Toads and frogs will breed there and make a racket all night long in spring and early summer as they call out to one another in love song. Do your best to ignore them. The presence of water in our outdoor living area provides untold benefits to the human users. Think about it: Why do so many of us travel to cottage country on summer weekends? You can bet that it has a lot to do with a primal instinct to be near water. It has this habit of calming us down. If the water is moving, as in a backyard fountain, waterfall or stream, so much the better. In addition to the calming effects, you will muffle out much city noise and the ambient sounds of urban life.
Mark Cullen is an expert gardener, author, broadcaster and tree advocate and holds the Order of Canada. His son, Ben, is a fourth-generation urban gardener and a graduate of the University of Guelph and Dalhousie University in Halifax.