There was a time when the only gravel gardens were in the desert. In lands of little rain where soils are porous and well drained, this surfacing material has proven highly successful. Problems arise when this solution is applied to other locations and climates that are not so compatible with the technique. With gravel proving popular particularly in contemporary landscape design, there are a few caveats to consider before you select it as a lawn substitute.
There is a dark side to gravel surfacing that raises its ugly head many months after it’s first laid out. These issues can turn a beautiful new project into a maintenance nightmare if you don’t make the right choices prior to installation.
GRAVEL IS KICKED OR TRACKED OUT OF PLACE
Photos of perfectly manicured gravel fields are rarely home to kids, dogs and active families. When there’s a lot of activity in the yard, gravel inevitably travels where it doesn’t belong because nothing really holds it in place. The early 20th century use of decomposed granite is rolled flat and packed into a dense layer that creates a hard crust so it’s not so easily tracked indoors to scratch your beautiful floors.
LITTER BUILDS UP
No matter where you live, there will be organic matter, from wind-blown lawn clippings to pine needles and autumn leaf drop. Fragments build up in gravel areas, making it impossible to separate from the pebbles. When using darker gravel hues such as black, and the steel grays so popular in modern design, this litter stands out like a sore thumb. Once contaminated, it’s impossible to resolve. To solve this problem it’s often recommended that gravels are earth tones so the litter doesn’t visually show up.
HEAVY RAIN RUNOFF
Everyone who has a gravel driveway knows what happens to it after heavy rain. A downpour can literally erode tiny riverbeds through gravel like it does in desert dry washes. Unless it’s repaired, raked and packed afterwards, that rivulet will simply grow deeper and cause proportionately more erosion after the next heavy rain. Be attentive to gravel areas during spring runoff and summer thunder storms.
CAN YOU RAKE IT?
Older gravel gardens left over from the previous exploration of this drought-busting technique tell us much about what works and what doesn’t. Larger gravel is hard to rake clean because so much organic matter, dirt and litter settles down between the pebbles to the surface that can be an inch or two beneath. Once this material accumulates it decomposes into a perfect humus for weed seeds to germinate. So even though you have weed barrier fabric beneath the gravel, this layer organic matter on top of it will foster whole crops of seedlings. It is best to use the finest gravel possible so it packs down tightly and is easily raked clean to remove litter. In the long term you may discover slab stones or precast concrete units are more manageable in lieu of lawns.
Beware that some of the same problems occur when you use gravel to fill the gaps between paving units. These too can be kicked out of place, invaded by litter, foster weeds and are impossible to rake clean unless carefully thought out in advance. It is wise to set the level of these fillers so they are below the edge of the adjacent paver to reduce some of the problems. Select small decorative gravels that pack together tightly to maintain a crisp joint.
When beautiful contemporary landscapes are featured in photography, it doesn’t tell you what’s required to maintain that great look. High-end homeowners can afford costly maintenance services to detail that gravel, but most folks have to do it themselves. Rather than becoming a slave to the darker side of gravel care, give some thought to your lifestyle when choosing size and color. Get that right and you'll be liberated from watering, raking and blowing away the chaff that is the root of problems that may not show today but are the inevitable side effect tomorrow.
Maureen Gilmer is an author, horticulturist and landscape designer. Learn more at www.MoPlants.com. Contact her at firstname.lastname@example.org or P.O. Box 891, Morongo Valley, CA 92256.