I love rock in the garden, but I particularly love gravel and other small rocks. I work them into nearly every design I create for my clients, as well as in my own landscape. Why the love affair with gravel? It serves many purposes, from solving drainage issues to lending textural appeal; it crunches under your feet; and it comes in many different colours and forms. Check out my favourites and see which one will work for you in your landscape.

Decomposed granite

The basics

Decomposed granite, or DG, is a granitic rock that has weathered to the point of breaking into very small pieces and silt-like particles. It comes in a reddish-tan colour that will fade to a lighter tan over time. Decomposed granite is ideal for pathways and rustic patios, and can also be used as a topdressing around arid plants. It’s sold by the cubic yard.

Advantages
It’s relatively inexpensive and readily available.

Disadvantages
It can track inside on the bottom of your shoes, so if you have hardwood floors, you might want to take your shoes off after walking on a DG pathway. It’s also difficult to remove weeds when they get out of control.

Special considerations

It’s best to apply it in thin layers, watering down and tamping each layer to create a very compact surface. You can also add a stabiliser (a water-activated binder) to the decomposed granite area, which protects the DG from the damaging effects of traffic and weather while still allowing it to be permeable.

Maintenance
You may consider installing a contractor-grade landscape fabric underneath your decomposed granite area to discourage weeds from growing, but be aware that weed seeds can still blow in from above. Stay on top of weeding by hand pulling or by carefully using an organic herbicide. DG will break down into the soil after a number of years, so you may find it necessary to add to your patio or walkway to keep it looking fresh.

Pea gravel

The basics

Pea gravel is a small, rounded rock that got its name because the rocks are about the size of a pea. In reality pea gravel comes in different sizes – 1/4 inch, 1/2 inch and 5/8 inch are common sizes. It typically comes in a range of tan, brown and white colour mixes, but do your homework to learn the cost of each. Use pea gravel for patio areas, pathways and filling in between flat rock, like flagstone.

Advantages
Most kinds are fairly inexpensive and readily available.

Disadvantages
It can be difficult to push a lawn mower or any wheeled equipment over a gravel path, as the wheels tend to sink into the gravel. It can stray out of place if not properly edged.

Special considerations

There are several different types of pea gravel, and some are significantly more expensive (rainbow gravel, for example). Be sure you know the difference when you are choosing your gravel to avoid sticker shock upon checkout.

Maintenance
Stay on top of weeding so it doesn’t become a maintenance issue. Pea gravel can have a tendency to stray out of its area if there’s no barrier to keep it in place, and even then, it can shift to cover nearby flagstone. Keep a broom handy to sweep it back into place.

River rock

The basics

River rocks are larger than pea gravel, typically 1 inch and larger in diameter. They’re available in a variety of colours, costs and sizes, and are used to create dry creek beds or to direct drainage through a property.

Advantages
It’s readily available in different types and costs.

Disadvantages
It can be difficult to weed through this type of rock; maintenance should be consistent so you can avoid unpleasant cleanups.

Special considerations

To create a realistic-looking dry creek bed, use different sizes of river rock with some small and large boulder accents – Mother Nature doesn’t limit herself to just one size rock.

Maintenance

As with other types of rock, stay on top of weeding, as once weeds get out of control, it’s very difficult to remove them. Use a blower to remove seasonal debris, like fallen leaves and soil. Installing landscape fabric underneath river rock is a great way to keep this heavier rock from settling into the soil below.

Crushed granite gravel

The basics

This one is closely related to decomposed granite, but it’s a bit chunkier in texture and size. While DG has quite a bit of silt and almost sand-like particles, crushed granite gravel has larger particles. The texture is not smooth like pea gravel, but this choice is perfect for walkways and patios, as well as for setting off xeric plants.

Advantages
It provides great texture in the garden, and is a step up from DG for gardeners who want a more refined or contemporary look.

Disadvantages
It can be hard to locate a source if you live in a more rural area, and it can be twice the cost of the similar but more humble decomposed granite.

Special considerations

It’s similar to decomposed granite.

Maintenance
The upkeep for crushed granite gravel is similar to that for decomposed granite and pea gravel, as it has some of the same qualities as each of those materials.