It is in the treatment of the margin that we make or mar a pond’s natural beauty. There is no one way in which native waters always meet the land, but there are some ways in which they never do. Nature never made broad borders of concrete or brick or hewn stone. Therefore avoid these in making a water garden. Rough stone walls are permissible at inlet and outlet only and even here they may be avoided if clayey soil can be had, provided the bank can be made proof against crawfish, which is most important. And in place of stones there will spring up beds of moisture-loving mosses, liverworts, and smooth sheets of Pellaea, whose delicate fruit-stalks shoot up in the first warm days of spring.
Beside the pond itself a path of gravel will enable us to come close to the water’s edge. Now we must bend away from the water and around the bog garden; now we cross It on a stone causeway or rustic bridge.
All around the grass and flowers run right out to the water’s edge. This is the essential point, and perfectly easy to attain. The water-tight construction of the bottom of the pond only needs to come up to the height of the desired water level. From this point a grassy bank may be raised as steep and high as one desires. Four to six inches above mean water level is high enough.
We can hide the junction of land and water completely by means of water-clover (Marsilia). This curious fern-plant, with leaves like a four-leaved clover, grows equally well in the wet edge of the sod or in the pond to a depth of eighteen inches. In the former situation the leaves stand up three or four inches, in the latter they float.