A Dirt-Cheap Alternative for Grounding Cover

Decomposed granite may be only a step above ordinary dirt, but this humblest of paving materials is seen in some very grand gardens--from the golden estates of the 1920s by designers such as Florence Yoch, to the most contemporary gardens by designers such as Nancy Goslee Power, currently working on the Walt Disney Concert Hall--which will have decomposed granite paths.

Landscape professionals love decomposed granite because it looks so indigenous to the garden, but can you do it yourself? Can you make your own natural looking paths or patios with just a wheelbarrow and the tools in the garage?

The answer is “nothing could be easier,” according to the contractors we talked to. Or cheaper.

A wheelbarrow, shovel, rake and a lawn roller are all you need (you can rent the lawn roller, sometimes even at a local nursery).

“D.G.,” as landscape designers and contractors call decomposed granite, is an inexpensive, gritty, crumbly, over-the-hill mineral that tends to stick together if it is compressed. They use it for paths and patios, even driveways, anywhere the look of a country dirt road or wilderness trail is wanted. It’s even tough enough to be used for equestrian trails.

Nancy Boswell of Mid City Granite in Los Angeles (a large supplier to contractors and building supply yards) tells us that theirs is dug right out of the Hollywood Hills on Forest Lawn property so it’s no wonder that the soft golden color looks right at home in our gardens.

There are other colors. In the Central Valley, they use a Sierra gray granite and there is a redder color that comes from Arizona, but in the L.A. area, most of the D.G. is an earthy yellow ocher, the color of our hills.

You can plant right through it (simply clear a little away) which really gives it that country lane look, with plants popping up in paths or the patio, like they might in nature. They appear to have simply sprouted there.

Weeds, on the other hand, are slow to sprout in the compacted D.G. If they do simply hoe them out.

Jerry Collins, a grading contractor in Tulare who uses a lot of D.G., says “nothing will grow through three to four inches of D.G., except maybe Bermuda grass.”

Pacific Palisades contractor Joan Booke has put many of her paths and patios where Bermuda grass lawns used to be, including her own. She doesn’t even bother to kill the lawn with herbicides (though the very cautious might first kill the Bermuda with an herbicide named Roundup), but removes all the turf with about four inches of soil and thatch and replaces it with three inches of D.G. This usually brings the thatch-fattened soil profile back down to where it ought to be. Collins points out another plus: “It’s considerably cheaper than concrete, or just about anything else.” Another contractor suggested that it is three to four times cheaper than concrete.

Booke has used it in elegant Brentwood gardens, on Silver Lake terraces and for driveways in Topanga (for driveways, it must be thicker).

She likes it so much she used it in her own garden, a ringing endorsement. The natural looking paths wind their way through the garden giving her easy access to all the flowering perennials she grows.

“It is not a permanent hard-scape (referring to the paving part of a landscape),” she said. “It does requires refurbishing every few years.”

To do so, you just add a little more. And, the fact that it is not permanent, could be seen as another plus. It allows you to change your mind later on.

Rain and sprinklers cause most of the wear and tear. “Don’t ever put a path under a downspout or where water can roll off the roof and down the path,” she said. A hard downpour will leave ruts in D.G. Sprinklers slowly wear it away, though in Booke’s garden one of the paths in already 5 years old and nearly as good as new.

D.G. is best on flat, level ground, and where it doesn’t get watered by the sprinklers.

Dry, D.G. tends to stay put. When wet, grains stick to shoes (some kinds are worse than others because they have more clay content), but it does not get muddy.

Despite this, “You probably won’t like D.G. if you have white carpets,” Booke said.

To keep it out of the house, end the D.G. paving before the house, at a patio, for instance, or a landing.

Contractors can make it very firm with a natural organic soil binder called Stabilizer, but usually they don’t. A very few building supply yards sell Stabilizer by the bag, or sell D.G. already mixed with it (for more information, call the manufacturer at (800) 928-2724).

Booke used Stabilizer on the Topanga Canyon driveway because it wasn’t level. In her own garden, she used plain D.G. brought in by the wheelbarrow load.

Paths and patios look best if the D.G. simply “melds” into the garden soil. Edgings ruin the effect of a natural path through the garden, though some designers use similarly colored stones at the edges of paths.

Use a lawn rake to tidy it up, or a wispy Japanese broom like Booke uses.

So how do you do it yourself? Simply remove about three inches of soil, lay down three inches of D.G., wet it, roll it with a lawn roller, wet it again and roll again. That’s all there is to it, according to Booke.

The rolling compacts the D.G. so it becomes almost like stone again.

Contractor Collins likes to “crown” the paths so they’re a little higher in the middle of the path and shed rainfall, and he simply lays it on top of the ground after first compacting the soil with a roller and raking it flat.

You can buy D.G. by the bag (about $3), or the cubic yard (about $30). A cubic yard will cover 120 square feet, three inches deep.

A skip load, dumped into your pickup or delivered, covers about 40 square feet, three inches deep, and a skip (which is about 10 cubic feet) costs around $10.

That will fill a large contractors’ wheelbarrow at least two or three times, and make a path four feet wide by 10 feet long, for 10 bucks. For covering ground, there’s not much you can buy that is so dirt-cheap.