With a remodel and a garden design project under way, I’ve been researching how to simplify garden maintenance and cut back on water usage. And I keep hearing more and more about the advantages of decomposed granite. Why? It turns out that in many ways decomposed granite (or DG, as it’s commonly called) is the ideal hardscape material: natural, permeable, aesthetically versatile, and wonderfully inexpensive.
After I started looking into DG, I began to notice it everywhere: The pretty little path through the local recreation field that never gets muddy? Decomposed granite. The soft, natural-looking driveway, where the surface stays put? Also decomposed granite. The mulch at the base of trees that keeps the ground weed-free? DG again.
Is DG the right material to choose for your hardscaping project? Read on:
What is decomposed granite?
See more of this garden at Before & After: A 1940s-Suburban House Grows Up Gracefully in Mill Valley, CA.
Decomposed granite is like gravel, but finer and generally more stable. It’s formed from the natural weathering and erosion of solid granite, a tough, hard, igneous rock. The DG sold as landscaping material is typically composed of fine three-eighths-inch (or smaller) particles; some may be no bigger than a grain of sand. Colors vary, from buff to brown, and include various shades of gray, black, red, and green.
For more garden design ideas, see Low-Cost Luxury: 9 Ways to Use Decomposed Granite in a Landscape.
What are the types of decomposed granite?
Although there are at least 30 colors and varying degrees of particle sizes, decomposed granite basically comes in three forms: natural, stabilized, and resin-coated.
- Natural DG is used as a mulch material and can be spread around trees and garden beds much like wood mulch. It will continue to weather after it is put in place and provides nutrients to surrounding soil and plants. It lasts longer than most other mulch materials and will not attract pests.
- For a path or patio, DG with stabilizers (which serve as a binder) is the best solution. Stabilized DG is often added on top of another gravel material, tamped down, then left with a thin loose layer on top.
- DG with resin for driveways has a similar surface to asphalt, but has a more natural look and is permeable.
What are the best ways to use decomposed granite?
While DG is most commonly used for paths, driveways, garden trails, and as a xeriscape ground cover, it can also be used to create smooth visual transitions between formal garden and wilderness. One of its advantages is that it breaks down, so any DG that migrates into lawn or planting beds does not cause problems the way gravel does. Lining a path or patio with a black metal strip (which will disappear if buried low enough) will help keep it in place.
One caveat: Make sure not to install the material too close to the entry of a house or building. It does stick to shoes, and will scratch floors. This can be avoided by separating the DG from the home with a few feet of other surface materials, plus a door mat.
How much does decomposed granite cost?
The raw material costs $40 to $50 per cubic yard and is available from landscape suppliers (and at stores such as Lowe’s and Home Depot). The cost to have a contractor install a path or patio is approximately $4 to $6 per square foot, depending on conditions and whether stabilizers are added. If you do it yourself, the cost will be about half that amount.
For a resin-coated DG driveway, which has a surface much like asphalt (but is permeable), the cost is higher. A local driveway installer is the best source for cost information.
See more of this garden in Before & After: An Artful Gravel Garden in Sonoma, California.
Considering a path that mixes DG with bluestone? Learn more about the options in Hardscaping 101: Pennsylvania Bluestone.
Decomposed Granite Recap
- Has some of the advantages of gravel–the crunchy sound, the softened look, the permeability–without some of the disadvantages: It remains firm underfoot.
- As it starts to weather and erode, it’s simple to add more.
- Soft, natural appearance.
- Can be used to smooth transitions between garden and wilderness.
- Provides good drainage.
- Excellent mulch material.
- Sticks to shoes–different surface materials are needed near a house, plus a doormat, to keep material out of house (will scratch floors)
- Good solution under large trees where grass won’t grow.
- Keeps dust down.
Planning a hardscaping project? See our Hardscape 101 guides to materials, including Pavers 101 and Gravel 101. And don’t miss our guides to everything you need to know about other materials, from Limestone Pavers to Picket Fences, in our Hardscaping 101 archives.
N.B.: This post was first published April 2014 and has been updated with new links.
Frequently asked questions
What is decomposed granite?
Decomposed granite is a type of finely graded granite that has been weathered and eroded over time. It has a sandy texture and is commonly used in hardscaping projects.
What are the benefits of using decomposed granite?
Decomposed granite offers several benefits such as its natural appearance, durability, low maintenance, and permeability. It can be used for pathways, patios, driveways, and more.
How do I install decomposed granite?
To install decomposed granite, first prepare the area by clearing any existing vegetation and weeds. Then, lay a weed barrier or landscape fabric to prevent weed growth. Finally, spread the decomposed granite evenly and compact it with a plate compactor or by watering and tamping it down.
Can decomposed granite be used for all hardscaping projects?
Decomposed granite is versatile and can be used for various hardscaping projects such as pathways, patios, driveways, and garden beds. However, it may not be suitable for areas with heavy foot or vehicle traffic as it may become loose or muddy.
How long does decomposed granite last?
When installed and maintained properly, decomposed granite can last for many years. However, its lifespan may depend on factors such as usage, weather conditions, and maintenance.
How do I maintain decomposed granite?
Maintaining decomposed granite is relatively easy. Regularly sweep or rake the surface to remove leaves and debris. Periodically add more decomposed granite as needed to fill in any depressions. If it becomes compacted or loses its texture, you can loosen it up by raking or adding water.
Is decomposed granite eco-friendly?
Yes, decomposed granite is considered eco-friendly due to its natural composition and permeability. It allows rainwater to penetrate the soil, reducing runoff and promoting water conservation. Additionally, it does not require the use of harmful chemicals for maintenance.
Can I plant on decomposed granite?
Yes, you can plant on decomposed granite. However, it is recommended to amend the soil with organic matter and nutrients to provide a better growing environment for plants. Additionally, choose plants that are suitable for well-draining soil conditions.
Can decomposed granite be used with other materials?
Yes, decomposed granite can be used in combination with other hardscaping materials. It pairs well with flagstone, pavers, and other types of stone. This allows for creative design possibilities and can enhance the overall look of your hardscape.
Is decomposed granite pet-friendly?
Decomposed granite is generally safe for pets. It is non-toxic and won't harm animals if ingested. However, keep in mind that loose decomposed granite may stick to their paws, so it's a good idea to regularly clean their feet after walking on it.