Waterfall Edging

Rock Steady

• Landscape rocks overhanging the water channel cover waterfall edging effectively. Place rocks so that they're stable. Black foam expanding sealant for use in ponds and waterfalls sticks rocks firmly to the waterfall liner, but it won't stick them to soil. Use rocks that match natural stone in the landscape. For a natural appearance, lay the rocks so that grains face the same direction and nest rocks. To nest rocks, dig shallow holes, set the rocks in them and fill in gaps with soil. Avoid arranging the rocks in a manner that could create a channel for the waterfall's water to spill out over the edge.

Gap Fillers

• Gravel, pebbles and cobblestones fill gaps between rocks and provide decorative cover. Mix 50/50 soil and three-quarters of an inch to 2 inches of gravel, and press the mixture into gaps between landscape rocks to help firm them in place. Cover the mixture with pebbles, cobblestones or gravel to improve the appearance and to prevent water washing the mixture away.

Formal Fringe

• Waterfalls with symmetrical steps, rather than natural looking steps, can look best with formal edging. Bricks, slate or pavers can be used to create a formal effect. Lay all the bricks or other materials loosely to check your design before mortaring them in place. Always wear gloves for mixing and applying mortar. A simple mix is 1 part cement, 1 part lime and 5 parts building sand, combined with just enough water to create the consistency of cream cheese. Use a trowel to apply mortar to the waterfall liner, and check the tops and sides of the edging with a level as you lay each piece.

Green Creepers

• Creeping ground cover plants provide attractive waterfall edging that slowly spreads to cover unsightly gaps. Blue star creeper (Isotoma fluviatilis) grows 2 to 4 inches tall and 12 to 18 inches wide, and it bears prolific, small, light-blue, star-shaped spring flowers. Hardy in U.S. Department of Agriculture plant hardiness zones 5 through 9, its tiny green leaves form a dense mat. Keep an eye on it thought because it is invasive in some areas, and has aggressive tendencies. "Quicksilver" Chinese wild ginger (Asarum splendens "Quicksilver") also provides effective cover, growing 1/2 to 1 foot tall and spreading indefinitely in moist soil. Named for its silver-highlighted foliage, "Quicksilver" is hardy in USDA zones 6 to 9. Water both plants regularly so that the soil is constantly moist, until they are established.