Water features are commonplace in formal gardens, and indeed, fountains were significant features in ancient Moorish gardens and, of course, at Versailles.
Casual plantings of bulrushes and other native waterside plants make excursions by boat along canals and streams especially enjoyable. And, of course, everyone loves the way forget-me-nots flower on the banks of streams, and water lilies enchant us on the surface of lakes and ponds. Monet’s paintings of water lilies in his home garden speak to us across the years.
Even if you don’t have room for a water feature, you may be able to grow moisture-loving plants in some low-lying spot in your yard that does not drain well, or you could create a rain garden.
Japanese iris, gunnera, rhododendrons, marsh marigolds, arum lilies, astilbe, day lilies, bergenia, phystostegia, primula, japonica, spirea, and globe flowers (that belong to the ranunculus family), all love moisture. Grow them on the banks of streams and ditches.
You might try forget-me-nots for spring bloom and then day lilies on a bank to bloom later. Both plants have the added advantage of securing the soil at the edges of water. Even a marshy eyesore can be transformed if you use plants that can tolerate having wet feet.