WRITTEN BY VALERIE EASTON PHOTOGRAPHED BY RICHARD HARTLAGE

	Assorted moisture-loving plants, including striped-leaf Canna 'Tropicana,' are rooted in pots sitting on shallow ledges around the pond margins to create a naturalistic blending of water and garden.

Digging a pond isn't quick or simple. It's one of those projects I assured my husband would take a weekend — and we dug, hauled dirt, and dug some more for most of a summer. But it was worth it (easy to say when I wasn't the one doing most of the digging). More than a decade later, the pond remains a low-maintenance focal point. It's also the most changeable and effective ground cover in the garden, mirroring the sky and teeming with fish, plants and bobbing glass balls that scuttle across the surface with the wind.
 

Now In Bloom Foliage plants carry the garden through the dry dog days of summer. Ligularia are large-leafed stunners, with a variety of foliage forms and colors. Once planted in the shady, moist spot they prefer, ligularia grow huge and showy. Ligularia dentata 'Othello,' above, adds a dramatic dark note to the late-summer garden with rounded, chocolate-colored leaves that have purple-red undersides. L. dentata 'Desdemona' is nearly indistinguishable from 'Othello,' but with maroon reverse on the leaves and spidery orange flowers rather than the more common yellow.

The fun and beauty, and for most gardeners the buzz of water gardening, is the expanded palette of plants that grow far more extravagantly than if they were on dry land. Whenever we think of plants for ponds, water lilies come to mind. But other options abound: Elegant papyrus lends a whiff of Egyptian exotica, and many of the irises, grasses and even canna lilies are perfectly happy with their pots set right into the pond. Which is one reason ours took so long to dig; forming underwater shelves at just the right depth to hold all those pots took a little while.

Water plants are more than decorative, for a pond or stream is its own ecosystem; plants play a large part in its health and vitality. Tufts and sprays of various kinds of plantings not only blend the water feature into the garden but help maintain the pond's ecology. Most can simply be submerged in their pots; canna lilies, Iris versicolor, Iris pseudacorus, Carex pendula and water lilies appear to be growing right out of the water, while in fact they're securely rooted in pots. Even the smallest pond or container can be spiffed up with a dwarf papyrus (Cyperus haspan) or a scattering of duckweed (Lemna minor).

The margins of a stream are naturally muddy, or a pond liner can be extended out to create a shallow bog. You'll be amazed at how quickly water-loving plants grow large to form the habitat around the water and stabilize its banks. Ornamental rhubarb (Rheum palmatum), hostas, callas, ligularia and ostrich-feather fern (Matteuccia struthiopteris) are all showy choices.

Oxygenators inhabit the regions beneath the surface, providing the oxygen fish and other pond creatures need. Because they float or root underwater, their stems and leaves lend habitat for fish eggs, tadpoles and baby fish. Despite the fact you won't see much of Parrot's feather (Myriophyllum aquaticum), hair grass (Eleocharis acicularis) or water crowfoot (Ranunculus aquatilis), they perform a vital function by diffusing oxygen into the water.

Floating plants remind me of those air-root plants they sell at state fairs; they are similarly unattached to soil. Roots and all, these plants float on the surface, creating a tapestry of foliage and flower, as well as shading the water to slow down algae buildup. Water hyacinth (Eichhornia crassipes), frogbit (Hydrocharis morsus-ranae), and greater bladderwort (Utricularia vulgaris) are all much prettier than you might expect from their names.

"The Encyclopedia of Water Garden Plants" (Timber Press, $49.95) is a new tome by experts Greg and Sue Speichert, founders of Water Gardening magazine. The book is the definitive reference on growing plants in water, and has enough color photos to inspire you to get to work. But remember, it'll probably take longer than a weekend.

Clarification: In the Aug. 1 Plant Life column, Valerie Easton mentioned two water-garden plants that state experts warn could be invasive. One, parrot feather, is causing problems in the Chehalis River. The other, frogbit, is a concern in Canada and East Coast wetlands. Specialist Kathy Hamel of the state Department of Ecology cautions gardeners against using any non-native aquatic plants without checking for invasive tendencies. She also warns not to release any such plants into natural waters, where they can be difficult to control. Check the department's Web site for a list of quarantined plants.

Valerie Easton is a Seattle free-lance writer and contributing editor for Horticulture magazine. Her e-mail address is valeaston@comcast.net.

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