Many of us in the Sierra foothills have gravel driveways, paths and roads. This can be a help to gardeners searching for more space to grow a colorful scheme of un-thirsty plants.
Using gravel as mulch over a garden bed has a fine long tradition in gardening style. In rainy Britain, gravel was used to create better drainage so coveted dry climate Mediterranean plants could be grown there. Two to three inches of gravel mulch reduces greatly the amount of weeding required. Some gravel gardens have a deeper layer of gravel, up to eight inches, and the plants thrive.
Gravel gardens could have had their origin in formal Japanese ‘dry landscape’ gardens located on the grounds of Zen Buddhist temples. The raked gravel was intended to limit distraction and give the impression that the landscape could be in any location, not only the existing one.
In the foothills, when we already have an existing expanse of gravel to deal with, plants can add a softening effect and add color and beauty to our neutral palette. We get all the benefits of good drainage and weed control, while growing all the vibrant Mediterranean plants that thrive here under drought conditions.
The good news is many of the plants suitable for a gravel garden are native and easy to find. The soft tones of Lavender, Santolina, Russian sage and California fuchsia contrast with the vivid colors of Ceanothus (wild lilac), Agastache (Hummingbird Mint,) Poppies, Autumn sage and Yarrow. These all the sharp drainage in a gravel-mulched garden. Don’t overlook sedums, grasses and any hardy herbs like common and creeping Thyme, Marjoram.
For a new gravel garden, remove all weeds from any garden bed, edge the bed with brick or stones and plant as you normally would, taking the full size of each plant into consideration.
Cover the ground with a two-to-three inch layer of half inch crush gravel and rake carefully. Other mulch options are decomposed granite, pea gravel, lava rock, river rock and slate chips. Even jewel colored glass gravel can be featured around small patio areas where they’ll be seen.
To construct an existing gravel driveway garden, simply pull back the gravel, dig a planting hole the size of your nursery can or root ball, tamp down the soil and replace the gravel which will now act as a mulch. Only amend the soil if your soil is pure clay or pure decomposed granite texture.
A drip system can be installed for plants that require what’s called ‘regular water,’ usually once or twice a week, three or four inches deep. However, for the drought-hardy plants listed here, hand watering once or twice a week in warm weather until they establish and less or none at all in a rainy spring or fall is all that’s required.
Take note of the heights that the plant are in full-size and plant the taller ones in back of the shorter ones, just like in any garden planting. If your gravel area is your driveway, plants that do not spread horizontally may be what you’ll plan.
Gravel gardens can be as small as a container garden with an inch of gravel mulch. Try this with interesting succulents like Sedum and Echeverias.
Each plant will stand out in a gravel garden, making the entire display a showcase feature in your landscape. Try raking the gravel around your planting area for a surprisingly neat and serene look. You’ll see that gravel can be gorgeous.
Sue Langley has a website, Sierra Foothill Garden, dedicated to gardening in our mountain community and can be emailed at firstname.lastname@example.org.