Stone is a fundamental element in every garden. Even if it goes unseen, in one form or other, rock makes up the mineral portion of the soil beneath our feet.
And, in many gardens, bringing in decorative stone adds structure and interest beyond compare. Plus, if you’re looking for a low maintenance garden, there really is nothing easier to care for in the garden than rock. It requires no watering, no fertilization, it won’t die, and in most cases, it requires no weeding.
Designing with stone may seem tricky, but given a little forethought, it’s actually easy and fun. Before you decide to add stone to your garden, consider a few things:
What purpose will stone serve in your garden? Wall rock, decorative boulders and patio stone can all be very different. When designing with decorative boulders, cluster larger groups together in a few key spots with plantings. Resist the urge to scatter lots of small stones about or it may look like a meteor shower hit your landscape. When choosing wall rock, look for large, dense stones that will stack without a lot of vertical seams, which create weakness. If you’re creating a boulder wall, remember weeds can easily grow between those cracks. And, before you start, be sure to check local construction regulations.
Where is your stone sourced? Landscape stone is shipped all over the world. It may come from India, Pennsylvania, Montana or somewhere else entirely. How far it travels can impact the price you pay as well as the environmental costs related to shipping it all over. Plus, some stone is pulled from mountainsides without care for the environmental impact. Ask about the material source before you buy.
How will your stone hold up over time? Some stones are denser – like granite. While other stones – like sandstone – are more porous. More porous stones may not work well in wet environments. They may crumble over time or they may become pitted with ugly growths that cannot be pressure washed away. Ask to see weathered samples of your favorite material before you purchase. Something freshly arrived at a stone yard may look very different from what it will look like after a few years in your garden.
Just want some gravel? Gravel paths and patios are relatively inexpensive and easy to install. Look for gravel made of angular particles that pack well. Materials like rounded pea gravel and river rock, which doesn’t pack, will bog down wheelbarrows and can become ankle twisters.
What shape of patio stone is right for you? Geometric or tile-cut stone lends itself to more formal patio designs. Plus, the cut seams are consistent and are fairly easy to fit together. Because labor has gone into cutting it, you may pay a bit more for pre-cut stone than you would for uncut flagstone. Naturally shaped flagstone can be fit tightly together, but you may need a rock saw to make a lot of cuts on your own. Or, it can be fit together more loosely. Regardless, putting a flagstone patio together is like working a jigsaw puzzle without a key, so be patient. When choosing stones, select thicker cuts of stone if you plan to create a permeable, “sand-set” patio. Thinner pieces are designed for jobs where the stone is mortared to another surface. And, remember: big pieces are heavy, but if you can lift them and set them into place, they won’t move around over time. Smaller pieces can look busy and often don’t stay put in a sand-set design.
Permeable or Impermeable? Sand-set or paverlay-set patios work great in many locations; these are permeable, meaning they let water pass through into the soil below. Some circumstances call for impermeable patio options that mortar stone together and keep water from passing into the soil below. Many cities regulate the amount of impermeable surface allowed on a residential site, so be sure to check your ordinances before you build.
Whether you’re adding some granite boulders to create the sense of changing elevations in your garden beds or you’re adding a stacked stone wall to hold up actual grade changes, stone can create year-round interest, texture and habitat in your garden. Chosen wisely and installed correctly, it will become one of the lowest maintenance, highest impact elements in your garden.