By Cindy Gilberg
Missouri is blessed with an abundance of water. Our ponds and wetlands, as well as the still pools within rivers and creeks, are filled with a wide array of native plants that love wet habitats. Water gardens look more in place than out of place with the surrounding natural environment when native plants are included as part or all of the plant palette, and these plants are well-adapted and quite hardy, so success is easily achieved.
Most of the native wetland plants available for water gardens are referred to as emergent or marginal plants, i.e. those that grow at the edges of ponds and rivers, or in wetlands. They will thrive as long as their roots have constant access to water. The water depth over the crowns of the plants can vary from 1 inch to 6 inches. When designing your water garden, create ample shallow areas or shelves where these plants can be planted. Include a waterfall that has small pools in the spillway to provide areas attractive to birds that come to drink or splash. Plants can be added to these areas within the waterfall to impart a more natural appearance and to soften the hardscape of the stone.
Pickerel weed (Pontaderia cordata) is perhaps one of the most beautiful natives for your water garden. It has striking, dark sky-blue flower spikes that are irresistible to many bees, butterflies and occasional hummingbirds. Its large, glossy heart-shaped leaves provide excellent textural contrast to the foliage of grasslike plants such as rushes and sedges. A mature plant attains a height of 2 to 3 feet and will delight gardeners with flowers from midsummer through autumn.
The aptly named arrowhead (Sagittaria latifolia) develops handsome, arrow-shaped leaves as it matures to about 2 or 3 feet tall. White flowers abound in mid-late summer. Known also as duck potato, this plant was prized by Native Americans who collected its large starchy tubers for food.
Rushes (Juncus sp.) are evergreen, grass-like plants, with many wetland species of varying heights present in Missouri. The soft rush (J. effusus) grows 2 to 3 feet tall and is a good choice when a strong vertical accent is desired. Create a striking textural combination by planting rushes flanked with pickerel weed or arrowhead. A plus is that dragonflies are attracted to the long, slender leaves of rushes as a place to rest.
Two of the four Missouri native irises are wetland species. The copper iris (Iris fulva) is a lesser known iris of an unusual reddish-orange or bronze color. The Southern blue flag (Iris shrevei) has medium to dark blue flowers that have delicately pale yellow veining on the falls (lower petals). The flowers appear in early summer and broad, sword-like leaves provide good texture. Both of these garden classics bloom in early summer, grow to 2½ feet and are true gems for the water garden.
Yes, there is a native water lily (Nymphaea odorata) and it is one that has been used extensively in the breeding of many hybrid cultivars. Of the plants described here, this is the only one that grows permanently submerged (1 to 2½ feet deep). The species name refers to the delicious fragrance that permeates the air during the summer and fall bloom season. Exquisitely sculptured white flowers nestle among the floating, rounded leaves that often serve as resting pads for young frogs.
This is only the beginning in the adventure of discovering native plants for your water garden. To gain inspiration for your water garden, visit some of the natural wetland areas around Missouri and, more locally, visit the Shaw Nature Reserve. Inquire at your local garden center for availability of these plants. Other sources may be found at MBG Kemper Center PlantFinder and at Grow Native.
Cindy Gilberg, horticulturist and Missouri native, founded and ran the garden center at Gilberg Perennial Farms with her husband Doug for 28 years, also teaching classes and workshops on gardening and garden design. She now focuses on garden design, consulting and teaching, and also works part-time in the Whitmire Wildflower Garden at Shaw Nature Reserve, emphasizing the use of native plants in home landscaping.