An interior designer put her skills to the test when she created living spaces outside her Connecticut home. Ellen Colonna has a thing for large hallways. "I think they're so gracious," says the interior designer, whose Connecticut home, circa 1830, boasts many. "I've never been one to conserve space. It's not my dictum. And I feel the same about land."

Perhaps that's why she chose to convert an overgrown marshland into a curvaceous tidal walk outside her home on Long Island Sound. "When we first moved in, we faced a messy bog full of weeds, some poison ivy and prickly bushes," Ellen says. "It was unsightly. We had to clean it up, but we knew we wanted to keep the marshland an estuary." She notes that "even when that area was in total disarray, the birds made it beautiful. We had egrets, all types of herons. We didn't want to disrupt their peace, but we wanted to be able to enjoy that area of our property, too."

That area, which runs along the west side of the couple's two acres, gave Ellen little inspiration until it was cleared. Then, with the help of landscape designer Ken Twombly, she set out to create a tidal walk whose winding paths would, like a center hallway, lead to various garden rooms.

"The beauty of working with Ken is that he operates much like an interior designer, picking plants and bringing them home to test in different areas of the garden," says Ellen. "As a designer, I know that a floor plan can be misleading. It isn't until you get in the space and start moving fabrics and furniture around that you get a true sense of what needs to be where. It works the same way with plants."

For the marsh walk, Ken created a canvas of groundcover and woodland plants such as hostas, ferns, sweet William, and pulmonaris, to which he later added color. A bay of lacecap hydrangea, in vivid blue and violet, occupies part of the garden, while a wall of white oakleaf hydrangea forms a backdrop for yellow daylilies.

"The most important thing for a garden in a marshy area is to find good, strong plants that survive year round, even when the tides are high," says Ken, "and make a path that won't deteriorate with salt water. We transformed a long sliver of property into a seaside walk, a garden for all seasons."

Woodland plants make unexpected statements along the marsh route. "I realize now the importance of giving your garden good bones-evergreens and woody bushes," says Ellen. They become the foundation, and you build from there." She and Ken incorporated dogwoods, holly, native roses, viburnums and itea to provide berries, seeds, and cover for the birds.

Along the woodland stretch are shady sycamores and maples, deep green American holly, and scattered crabapple trees. "Crabapples are great for marshy areas, and they do get soaked in salt water because they're right on the edge," she says. "But in spring, they provide the most beautiful pink color to the tidal walk."

The path, made of cedar wood chips, meanders through various areas Ellen calls her garden rooms. The plants there thrive as a result of leaf mulch she says is perfect for the marshland. "When the leaves compost, the mulch turns into the most incredible soil," she says. "It's like black gold. You may not want to use in your formal garden, but if you're going for the natural look, I highly recommend it."

Beyond one end of the path lies a swimming pool, pool house, and an expanse of grass where the boys play ball. "I needed a taste of formality in my garden as well, so when we added the pool, I went to work adorning it," she says.

At the footpath's other end sits a pair of teak chairs, where Ellen and her husband watch their sons splash in the marsh water. "This is their playground," she says. "I suppose it's mine, too."