What the size label on a pile of gravel actually means
Before you can pick between 3/8 inch and 3/4 inch rock, it helps to know that neither number is a measurement of the stone in front of you. Both are screen sizes. Rock sold as 3/4 inch typically contains pieces running from about a half inch up to about an inch, with the bulk of it clustered near the 3/4 mark. Rock sold as 3/8 inch works the same way at a smaller scale, with a spread of pieces around the nominal size.
That spread matters more than the label does. Two suppliers can both sell you 3/8 inch rock and one load will feel noticeably finer underfoot than the other, depending on where the screen cut off and how much fine material rode along in the pile. When you are trying to predict how a material behaves in wind or under a wheelbarrow tire, the range is the useful piece of information, not the fraction on the sign.
Our landscape material calculator does this math for you. Enter the area and depth and it returns cubic yards to order.
Suppliers around Albuquerque commonly carry river sourced rock in 3/8 inch, 3/4 inch, 1 1/2 inch, and 2 to 4 inch, usually in both a round gray and a crushed gray. The larger sizes have their place as accent rock, in dry creek beds, and in erosion control. For the everyday job of covering a front yard, a side yard, or a set of planting beds, the real decision almost always comes down to the two smallest options.
Shape deserves as much attention as diameter. Round river rock rolls. It settles into a loose layer that shifts when you step on it and slides downhill given any encouragement. Crushed rock has broken flat faces that catch on each other and lock into a firmer layer that holds a slope. If you are torn between 3/8 and 3/4 for a bed with any pitch to it, choosing crushed instead of round solves part of the problem on its own.
Key takeaway: smaller rock reads from the street as a smooth even carpet. Larger rock reads as texture, with visible shadow between the stones. Neither is more correct. They just do different things to a yard, and they behave very differently once the spring wind starts.
Wind scatter, the deciding factor for a lot of ABQ yards
Spring in the middle Rio Grande valley brings weeks of gusty afternoons at a stretch. If you have lived here through a March and April, you already know the pattern. That season is the single best test of a rock choice, and it is where 3/8 inch and 3/4 inch part ways.
To be clear about what actually happens, 3/8 inch rock does not lift off the ground and fly like sand. Individual pieces are too heavy for that. What it does is migrate. Over a season it creeps off the crest of a mound, drifts toward the downwind side of a bed, and ends up on sidewalks and driveways through a combination of wind and foot traffic. Nobody watches it happen. You just notice one summer that the mound looks thin on one side and there is a fan of small stone across the concrete.
Rock at 3/4 inch is heavy enough per piece that wind alone rarely relocates it on flat ground. It will still move if water is running across the bed during a hard monsoon storm, but ordinary gusty weather leaves it where you put it.
The bigger risk with small rock is not the scatter itself. It is what the scatter exposes. Once a thin spot opens on the high point of a mound, you are looking at fabric or bare soil, and the sun and wind work on that spot faster than on the rest of the bed. The thin area spreads outward instead of healing. That is why a small rock yard tends to look fine for two years and then suddenly look tired.
If you want the finer look, the practical fix is zoning rather than compromise. Keep 3/8 inch on flat, edged, contained beds. Use 3/4 inch or larger on berms, on slopes, and on any strip that runs along a driveway or out to the street edge where wind has a clear run and tires kick material out.
Edging earns its cost with the small stuff. Metal edging, a paver border, or a bed edge recessed slightly below the surrounding grade all keep material from walking out over time. With 3/4 inch rock you can sometimes get away with a soft edge. With 3/8 inch, plan on a hard one.
Heat against stucco and south or west walls
Rock takes on heat through the day and gives it back into the evening. That is true of any mineral mulch, but the effect is easy to underestimate against a wall.
Light colored gravel reflects a good share of the sun back upward, at the wall and at anything planted in the bed. A west facing stucco wall with pale rock running right up to it carries a double load. Direct afternoon sun hits the stucco, and reflected light comes up off the gravel underneath it. The wall and the air right in front of it stay hot well past sunset.
Size plays into this in a small but real way. Fine rock packs tighter and presents a continuous, uniform surface that behaves more like a mirror. Larger rock has deeper voids and more shadow between pieces, so a little less of the light bounces straight back up. It is not a dramatic difference, but if you are already leaning one direction for a hot wall bed, it is a nudge toward the larger size.
When shrubs or perennials struggle in one of these beds, the reflected heat is usually the culprit, not the rock as a material. You have two straightforward responses. Choose plants that genuinely handle reflected heat, which in practice means the tough desert adapted species rather than the ones that merely tolerate full sun. Or pull the planting a few feet off the wall so the worst of the bounce misses it.
Darker gravel flips the trade. It absorbs instead of reflecting, which is easier on nearby plants, but the bed surface itself gets hot enough to be unpleasant underfoot and it radiates more heat back out at night. If the bed is somewhere people walk barefoot on a summer evening, that matters.
One detail worth holding onto regardless of size elsewhere in the yard. Keep a clear band of rock right along the foundation, with no plantings and no organic material piling up against the stucco. Larger rock does that job better because it does not pack down into a mat that holds moisture at the wall.
Weed seeds, voids, and how deep to go
The most useful thing to understand about weeds in a rock yard is that they mostly are not coming up from below. They come from seed that blows in, lands on the surface, and germinates in the fine dust that collects between the stones. Once you accept that, the fabric question and the depth question both get simpler.
Rock at 3/4 inch has larger voids between pieces. Blown in seed and accumulated dust tend to fall down into the layer rather than sitting in a shallow seedbed at the top. Those deeper voids also dry out quickly after a rain, which is hard on anything trying to sprout.
Rock at 3/8 inch has a tighter surface. It is tempting to read that as more of a barrier, but it works the other way around in practice. Fines that settle on a tight surface stay on top and behave like a thin layer of soil. That film is exactly where the goathead and tumbleweed seedlings you pull every July get started.
Depth does more for weed control than diameter does. A thin scatter of rock over fabric holds back almost nothing. As a working target, go about 2 inches for fine rock and closer to 3 inches for 3/4 inch and up. Larger stone needs the extra depth simply to form a continuous layer with no gaps opening down to the base.
The monsoon is the other half of the equation. Whatever germinates in an Albuquerque rock yard mostly does so after the first real storms of late summer. Plan on a cleanup pass in August rather than assuming the rock will handle it for you. Pulling seedlings when the ground is still damp from a storm is far easier than chipping them out of dry gravel in September.
Do you need fabric underneath
Landscape fabric helps in one specific way that is worth naming. It keeps rock from sinking into soft soil and slowly disappearing over the course of several years. On a sandy or loose base that is a genuine benefit, and it is the strongest argument for using it.
What fabric does not do is stop the weeds that actually bother you, because those germinate above it in accumulated fines. People install fabric expecting a weed free yard and then feel cheated three summers later when they are pulling seedlings that are rooted in a quarter inch of dust sitting on top of the barrier.
The trade off is that fabric is a nuisance to live with. Any time you want to add a shrub, move a plant, or run a new drip line, you are cutting and patching. Every cut is a spot where the edges fray and the rock starts working its way through.
In planting beds where you expect to change things, a lot of homeowners are better served by skipping fabric, going a bit deeper on rock, and pulling the occasional seedling. In pure hardscape zones, a foundation band or a strip along a driveway where nothing will ever be planted, fabric is much easier to justify.
Either way, fabric is not a substitute for depth. Depth is what shades the base and keeps germination from getting going in the first place.
Tons per 100 square feet at 2 and 3 inch depths
Here is the math that turns a decision into an order. Landscape gravel generally runs somewhere near 1.4 to 1.5 tons per cubic yard, so the numbers below use about 1.4 tons per yard as a working average. Ask your supplier for the actual weight of the specific rock you are buying, since river rock and crushed stone are not identical and a heavier product changes the tonnage.
The math behind the numbers
One hundred square feet at 2 inches deep is about 0.62 cubic yards. At the working average that is roughly 0.85 to 0.9 tons.
One hundred square feet at 3 inches deep is about 0.93 cubic yards, which comes out to roughly 1.3 tons.
Scaling from there is straightforward. A 500 square foot bed at 3 inches lands in the neighborhood of 6.5 tons. A 1,000 square foot front yard at 2 inches is somewhere around 8.5 to 9 tons. Those are planning numbers, not guarantees, and they assume you are covering flat ground evenly.
Add a cushion on top of whatever you calculate. Uneven ground, settling into the base, and the simple fact that rock never spreads perfectly flat all eat material. Running a quarter ton short after the truck has left is a much worse afternoon than having a small pile left over by the side of the house. Leftover rock always finds a job.
One more adjustment. Larger rock covers slightly less ground per ton at the same nominal depth, because you need more depth to close the gaps between pieces. If you are going 3/4 inch or bigger, budget on the high side of your estimate rather than the low side. Running the numbers through a bulk stone delivery in Albuquerque quote with your square footage and target depth in hand will get you a much faster answer than guessing at the counter.
Ordering in tons versus yards
This trips people up constantly. Most bulk suppliers quote stone by the ton, while mulch and soil go by the cubic yard. If you have shopped bark mulch before and you are now pricing gravel, you are comparing two different units and the per unit numbers will not line up.
Know which unit you are being quoted before you compare two suppliers. A price that looks better by the ton may not be better once you convert. And when you place the order, state your number in the unit the supplier uses so nothing gets translated twice.
Picking one, and a few Albuquerque specific calls
Choose 3/8 inch for flat beds with solid edging, for a smooth uniform look, for narrow side yards, and for anywhere you want a surface that is comfortable to walk on without shoes. It is the size that reads as tidy and finished from the curb.
Choose 3/4 inch for berms and slopes, for driveway and street edges, for the band along the foundation, for drainage swales, and for any bed where the spring wind has a long clear run at it. It is also the safer pick if you are not planning to babysit the yard much.
Mixing sizes across one property is completely normal and looks deliberate as long as you keep it to defined zones. Fine rock in the enclosed courtyard, larger rock on the berm and along the drive. What looks accidental is random patches of two sizes with no logic connecting them.
Crusher fines are worth knowing about as a separate product rather than a third size option. They compact into a firm walkable surface and make good paths, but they are not a mulch. They shed water rather than letting it soak in, so they belong on paths and seating areas, not spread across planting beds.
Go look at a stockpile or get a sample before you commit to a color. Rock looks like a different material wet than dry, and different again under full midday sun than in a shaded supplier yard. A front yard is a lot of square footage to regret, and once it is spread, changing your mind means moving every ton of it twice.
Finally, think through the logistics before the truck arrives. Where the pile can be dropped, how far the wheelbarrow run is to the far corner of the yard, and whether a gate is wide enough all affect how the job goes. If the haul is long, it is often smarter to split a large order into zones and take delivery in stages rather than staring down one enormous pile in the driveway with a weekend to move it.
How We Started
We started Mulch Mound because we got tired of the hassle that came with buying landscaping materials. The options were either loading bags into your car at a garden center or calling around to local suppliers, trying to figure out pricing, minimums, and delivery schedules. Neither option felt convenient or transparent.
Three of us – Alec, Mo, and Tyler – decided there had to be a better way. Alec and Tyler got their start back in 2013 running a landscaping business during college, moving mulch and mowing lawns to pay tuition. That experience taught them how frustrating it was to source materials, and years later, that frustration turned into Mulch Mound.
We focus on making it simple to get mulch, stone, and soil delivered directly to your home. Order online, pick your delivery date, and we handle the rest. No loading bags. No calling multiple suppliers. No wondering if you bought enough or paid a fair price.
We work with quality local suppliers in the areas we serve and aim to be straightforward about what we offer and what it costs. Landscaping is hard work. Buying the materials for it shouldn't be.
Frequently asked questions
What size gravel is best around a house foundation?
Go larger, 3/4 inch or up, in a clear band roughly a foot wide against the wall. Larger stone stays in place when water sheets off the roof during a storm instead of washing into a ridge at the edge of the drip line.
It also refuses to trap leaf litter and organic debris tight against the stucco the way finer material does, and it lets water move down through the layer and away from the wall rather than holding moisture right where the stucco meets the ground.
Will 3/8 inch gravel blow away in spring wind?
Whole pieces rarely lift. What you notice instead is two separate things happening. The layer migrates gradually toward the downwind edge of a bed, and the fine dust that came with the load blows out of the surface, which dulls the color and thins the tops of any mounds.
A useful trick on a fresh small rock install is to hose the surface down once after spreading. That knocks a lot of the loose dust down into the layer where it cannot blow off, and the rock holds its color noticeably better through the first spring.
How do I stop rock from ending up in the street?
A recessed edge works better than a raised one. If the finished rock surface sits slightly below the level of the sidewalk or curb, wind and running water have no lip to push material over. A raised border, by contrast, gives blown rock a ramp and gives water a place to pool and then overtop.
The same logic applies at driveway edges. Setting the rock surface a touch low also keeps tires from flinging stone every time someone cuts the corner.
Can I put new rock over old rock?
Usually yes, if the existing layer is reasonably clean of weeds and organic buildup and you are simply adding depth in the same size. That is the easiest refresh there is.
Switching sizes is where it goes wrong. Dumping 3/8 inch into an existing 3/4 inch bed fills all the voids and leaves you with the drawbacks of both, a tight dusty surface with no drainage benefit. If you are changing sizes, pull the old material out first.
How long does landscape rock last?
As a material, effectively forever. Nobody replaces gravel because the gravel wore out. What ages is the look, as windblown fines settle in and leaf litter, seed pods, and general debris build up on the surface until the color goes flat.
A vigorous raking and an occasional rinse with a hose resets most of that. Every several years you may want to add a fresh partial layer on top to bring the depth and the color back, which is a far smaller order than the original install.