Comparing Gravels for Landscape Installation
photo credit: tali wildman
We love using gravel in our landscape installations. We spec it on every project as a lovely composition with steel, wood, concrete, turf grass, and vegetation. For a while we used mulch in vegetative beds (and I know our build team would prefer to move it over heavy gravel), but we found that gravel was preferable as a surface treatment in most applications for a number of reasons:
Maintenance. Gravel does not need to be reapplied each year (except for topdressing where the ground plane has settled) nor does it move as easily with storm water. It’s easier to blow leaves out of, especially when stabilized with polymeric sand.
Appearance. Gravel color stays consistent while wood mulch will fade in the sunlight.
Weeds. Wood mulch breaks down and adds organic matter, allowing for weeds to germinate, while gravels discourage the errant opportunistic seed.
Water. Gravel does a fine job of covering exposed soil, especially when installed over landscape fabric, to retain moisture.
Design. Gravel implies a path much more clearly than wood mulch, and creates a space when framed with furniture, vegetation, walls, and steel edging. It also works better with sparse xeriscape planting.
During a consultation, we ask our clients how they want to use the space. Programming informs our design decisions and material choices. There are certain criteria that I’ll expand on in pros/cons below that make one gravel choice more preferable over another.
Will you be barefoot?
Is there or will there be a pool?
Are there dogs or small children that might move the gravel?
Do you want to dine at a table, or sit at a couch? Will the chairs move?
Is there slope or drainage we need to address?
Do you expect users to have limited mobility?
Will you be maintaining the area yourself or having a crew come in periodically?
Below are the gravels available in and around Austin, TX. We have experience working with each of these aggregates and gathered feedback from clients after extended use. We always recommend using heavy-duty steel edging instead of leaving two loose materials butting up against each other – the maintenance headache alone has proven that this durable material does more than simply add another visual element.
Decomposed Granite – Naturally decomposed; usually has clay mixed in. This is the most common material used for paths in park spaces and for low-cost landscape installations. Brown/dark tan in color.
Pros: Compacts really well, providing a stable surface for paths and driveways. Best used as a base for other gravels, especially because of its inexpensive price point.
Cons: Tracks in on shoes / paws and can scratch wood floors; erodes even on a minor slope or in the path of storm water; weed-prone. Not barefoot friendly.
photo credit: casey dunn
Limestone Screening / Crushed Limestone – Sedimentary rock that is composed of the minerals and skeletal fragments such as coral and mollusks; white or creamy in color and screened for consistent sizes for landscape application.
Pros: Resists weed growth; barefoot-tolerable with the smallest sized screenings; neutral color palette for modern landscape installations. Works for furniture that will not be moved around (like couches or benches at a table). Depending on compaction, can provide good drainage / is water permeable; resists weed growth.
Cons: Very reflective and better used in at least part-shade. Can raise the pH of soil. Compacts for use in patios and living spaces. Sometimes the product looks more creamy than white, depending on the quarry. Can track by foot if a very small size.
Mexican Beach Pebble / Mexican Moon Pebble – Hand-picked beach pebbles from the Baja area; has a smooth finish and dark grey color.
Pros: Works as a neutral accent to a landscape where erosion is an issue, similar to river stone applications. The shape adds a nice contrast to smaller aggregates.
Cons: Polished varieties can be very pricy; the size is not suited for paths or patios.
Pea Gravel – Small, round gravel. Has warm tones like browns, pinks, and creamy shades mixed in.
Pros: Barefoot-friendly; good drainage; easily maintained with a rake. Works best for furniture that will not be moved around (like couches or benches at a table).
Cons: Shifts underfoot and feels a little sloshy; difficult to drag wheeled items through it.
River stone – Native Texas river gravel ranging in size from 3”–5”. Mulit-colored stones with light pinks, grays and light browns.
Pros: Great for drainage and maintaining slope. Can be used to collect water around eaves without gutters and in conjunction with a french drain.
Cons: Unsuitable as path or patio material. Generally too large and indelicate as a gravel mulch, unless with larger or more established plants and those appropriate in dry creek beds.
Texas Basalt / Tejas Black / Black Star – volcanic rock that is dark grey; turns black when wet.
Pros: Not reflective; neutral color palette for modern landscape installations. Stays in place and compacts slightly better than limestone for use in paths, patios, and driveways. Works for furniture that will not be moved around (like couches or benches at a table). Doesn’t track in like DG or crushed limestone. Good drainage; doesn’t decompose; resists weed growth.
Cons: Absorbs and retains heat. One of the pricier gravel choices.