Pathways with Purpose
We may take indoor floors for granted, but special surfaces underfoot outdoors often surprise us with their bold statements. As shelter for your feet, hard surfaces made of stone can't help but make a garden feel more welcoming. Stepping-stones set in grass say "Come this way," and a stone patio splashed into a sunny spot of your yard says "Bask here." Outdoor floors and paths clearly define the places meant for people rather than plants, and they make your featured plantings more accessible and easier to enjoy.
Walkways Up Front
A spacious expanse of stone just outside your front door breathes its beauty into everything around it and firmly connects your home to the solid earth. Whether you use it to widen a long walkway as it nears the entrance or to create a wide platform at the base of your front steps that feels like a welcoming patio, entryway stonework sets an elegant style that's easy to amplify with graceful plants. Large containers that coordinate with the colors of the stone can be planted with splashy annuals, and you can use low-growing evergreens to add textural interest that will remain constant through the seasons.
Safety, comfort, and stability are top priorities for a front walkway, followed closely by curb appeal. A handsome front walkway enhances the value of your home while giving everyone who sees it a fleeting wave of pleasure. Front walkways, likely to be used by guests wearing their "good" shoes, need to be both smooth and wide. Walkways more than 3 feet wide are ideal, since they make it possible for two people to approach walking side by side. In northern areas, they need to be made in such a way that they can be kept clear of ice and snow in winter.
Smooth flagstone walkways create the clean, organized effect that we call formal, which is what people often want in their front yards. You will get the most formal look by using a single type of cut stone laid in a distinct pattern. The pattern may be subtle or very pronounced, depending on the look you want to achieve. There is no right or wrong way for you to do this, only endless creative opportunities, including the ones I'll describe here.
Plan in advance for some type of edge that will serve as a visual frame for your stonework. Neat, uniform plants such as liriope, candytuft, or ajuga are ideal, or you can use an evergreen ground cover such as English ivy or pachysandra.
If your home is brick, you can use brick to frame (or edge) your walkway, and possibly include brick in your stonework pattern as well. Both brick and stone can be dry-laid, but brick edgings stay put better when mortared into place. In fact, a mortared brick edging does an outstanding job of framing dry-laid stone.
An edging made of cut stone, laid on its side, also provides structural support. Or, if you want to evoke the feeling of a stream, you can arrange rounded stones around the edge of your walkway after it is finished, keeping in mind the way nature likes to tumble river rocks into scattered groups.
In the walkway itself, formal patterns often encompass a central line, or spine, made up of large stones that are sufficiently organized to impart a noticeable rhythm, flanked by a less disciplined pattern along the edges (see top right drawing below). In addition to looking handsomely refined, stone walkways structured this way are often more economical to build, because you can sink your money into pretty precut stones for the spine and use another less costly (or found) stone for the outer edges.
You can also pursue patterning differently, by using smaller stones in the center of the walkway and employing larger ones to establish a strong outline along the outer edges of the walk (see bottom right drawing below). This approach also is helpful where drainage is uncertain, because water that accumulates on the walkway can seep down through the many crevices between the small stones set in the middle.
Making New Walkways
Before your heart becomes firmly set on a stone walkway, you'll need to study exactly how walkways are built. Preparing the site often requires as much time and care as setting the stones, but it is not extremely difficult as long as you understand what you are doing. Of course, the degree of preparation depends on whether you are laying stones in turf or mortar or creating a dry-laid walkway. Because the latter approach is the one most often chosen by gardeners who want to make new walkways with their own hands, it is the one I will explain in detail. Also note that the same steps used to prepare a site for dry-laid stone apply to making gravel or pebble walkways capable of standing the test of time.
First I'll introduce you to the materials and what they do, and then we'll go through the installation process step by step. Study both the mental and the physical aspects of creating a walkway before you get started, and you can be assured of success.
Before you can budget your time and money, you'll need to weigh the pros and cons of different materials. The first decision, of course, is choosing the paving material itself. Paving stones that are more than 3 inches thick, such as flat pieces of fieldstone, are heavy to handle, but because of their weight, they hold their position very well. This means the foundation beneath the walkway does not need to be as deep as if you were using 2-inch-thick pieces of flagstone. After choosing your paving material, measure its thickness, because this factor influences both the depth of the foundation and what you will use to fill the crevices between the stones.
In any climate, using any type of paving stone, you will need to excavate a foundation for your walkway. The foundation is filled from the bottom up with a layer of fine gravel, then a layer of paver base (also known as crushed rock - see the box below for the different terms used for these materials), and finally your paving stone of choice. The purpose of the foundation is threefold: It aids in drainage; provides a bed for the stone; and, in cold regions, expands and contracts when the surrounding soil freezes and thaws, reducing the likelihood that your paving stones will sink down or pop up in response to changes in the weather.
In climates where soil freezes more than 6 inches deep, the foundation needs to be 12 inches below the surface. After excavating the site to this depth, measure the thickness of your paving stone and add 2 inches (the depth of the middle layer of paver base) to that number. Subtract the total thickness of these two layers from 12 inches, and you will know how deep a layer of fine gravel you need to place in the excavated site.
In climates where the soil seldom freezes, or freezes only 4 inches down, the foundation need not be as deep. However, you still need the enhanced drainage from the gravel base and the excellent seating you get from the middle layer of paver base. In USDA Hardiness Zones 7 to 10 (see map, page 232), a base layer of 2 inches of gravel is sufficient. This means that if you are using 2-inch-thick stone, you will need to excavate only 6 inches deep - 2 inches for the gravel, 2 inches for the paver base, and 2 inches for the stone.