What Are the Main Types of Gravel Used For Landscaping?

Gravel can be used for a variety of Landscaping projects, and can turn almost any outdoor space from looking drab to modern and clean. While prices of gravel vary, most homeowners and landscapers alike can agree that gravel is a fairly cost affordable, and versatile option for those who are looking to spruce up their space, without having to change a ton of things in their yard.

If we haven’t met before allow us to introduce ourselves. We are Back 40 Landscaping and our expertise is in retaining walls and hardscaping. We also like to bring education to those looking for gravel solutions.

What Can Gravel Be Used For?

First, let’s touch on what purpose gravel serves for landscaping. Gravel can be used to build parking pads for R. V’S., trailers, trucks, cars, lawn mowers, machines, and even to put storage sheds on. Gravel driveways are extremely popular, especially on large areas such as long driveways.

It can also be used in edging for gardens, as a walkway to get from point A to point B anywhere on your property, or even a place for your dog to have their own spot outside.

The possibilities of what you can do with gravel are endless.  

What’s even better, gravel is much more cost effective to use than pavers or concrete for most projects, the job can be done quickly, and with proper planning little damage will occur in the surrounding areas.

What Are the Different Types of Gravel That Can Be Used?

The three main shapes of gravel that are used for landscaping jobs are minus, clear, and round rock. Almost every supplier will call it something different, and there are numerous slang terms to keep in mind.

Along with the different shapes of gravel, you can get different sizes, and colors. Gravel colors are predetermined by the mountain they are blasted from, or river they are dredged from.

Minus Material

Type / Name

Minus material (sometimes called road-base) gets its name from having smaller material in its mix. ¾” minus will contain ¾” gravel with small pieces. Nothing will be bigger than ¾”.

Likewise, ½” minus will not have anything bigger than ½” and will contain smaller pieces as well.

Physical Properties

Minus and clear material are both angular in nature. They are fragments of blasting or crushing. The angular shape is what allows them to lock together when compacted.

Options range in size from 3/8” minus to about 3” minus. Anything bigger than that is not typically used for landscaping.

Compaction

The minus pieces are what makes this the best material for compacting. The minus material gets compacted in between the larger material and it becomes completely uniform and similarly as hard as concrete.

Expect a layer 6” thick will compact about 1” - 1.5” depending on compaction equipment.

Pros

• Compacts the hardest out of all three types of Gravel
• Provides the most uniform surface for wheeling strollers, lawn mowers etc. over it
• Very stable footing, and most like concrete when compacted and raked smooth

Cons

• The smaller pieces will track around a little bit, and you will find them in the near vicinity. They get carried by way of foot, vehicle, and animal traffic, similarly to sand at the beach coming home on your shoes
• Does not drain as well as material with void spaces such as clear material or round river rock
• The finer material can splash up onto vehicle rims while washing

Typical Uses

This is a great option for walking paths, driveways, parking areas and anything else you want a sturdy, hard surface. It’s used in the construction industry under concrete, asphalt and any other situation you want a highly compactable surface.

Color

The color of minus material gravel will vary depending on the supplier, mountain it came from and batch. You cannot expect gravel to have an exact color, as veins in the mountain are constantly changing.

IN GENERAL Abbotsford has blue/grey rock, Mission has sandy brown rock, and Chilliwack has darker almost black rock.

Also increasing in popularity is the recycled material industry. Crushed and ground up concrete is just as uniform, long lasting, and available. Recycled products are usually cheaper, however they are a grey concrete color and not a bright vibrate natural rock color that may be desired.

If color matching existing gravel, or you are concerned about the color you should make this very known to your landscaper, so your expectations can be met before the gravel is delivered.

Clear Material

Type / Name

Clear material (sometimes called clean rock) is a product that contains no fines (small particles). All of the pieces are the same size. ¾” clear contains only ¾” material.

Physical Properties

Clear gravel is angular and jagged in shape. This rough & random shape gives a great visual depth while looking very uniform. The most used sizes are between 3/8” – 10”, although smaller and larger feature rocks are available.

Compaction

Clear gravel requires very little to no compaction. Because it is all the same size effective compaction is usually achieved by simply dumping it in place. Contained clear gravel obtains 95% compaction simply by placing the gravel. To achieve 98% compaction (a typical engineer requirement) further compaction is required. This is extremely beneficial in areas that you cannot get a compactor, a compactor would cause damage to existing structures, or you would like to save the time and cost of compacting.

It would be very difficult to get a compactor behind this wall, yet it needs to be backfilled with gravel.

In this case because of the need for gravel, good drainage, and not able to get a compactor behind it, clear material is an excellent choice here.

Pros

• Provides an excellent stable surface
• Compaction is virtually optional
• Drains fantastic, as there are lots of void spaces between rocks
• Due to its weight, it does not track around as much finer materials. An often-overlooked aspect when near homes entrances
• Excellent material to wash a vehicle on, as there will be no sand or finer materials splashing up onto the rims.

Cons

• Does not compact as tight or as hard as material with fines
• Does not provide as uniform of a surface, and will be a little harder to wheel strollers, lawn mowers, or anything else across it.

Typical Uses

• Clear material is typically used in projects where good drainage is required. The combination of good drainage and strong structural properties make is an excellent building block for under and behind Allan Block retaining walls.
• Driveways that are not abnormally steep
• Parking lots, and parking areas.

Color

Just like the minus material local quarries will affect the color of your clear material. 

River Rock

River rock may as well be in a league of its own because it is so different. It’s mainly used for decorative purposes, or in drainage applications.

Type / Name

River rock is sometimes called round rock.

Physical Properties

Just like its name implies it is a smooth round, oval rock. It is commonly used in sizes 1” – 12”, although smaller and larger sizes are available.

Compaction

River rock will not compact, or lock together. If used for a driveway it will constantly move around, and show tire ruts. It should not be used in a structural capacity in most cases.

Pros

• Looks great in a decorative setting
• Very natural looking when used in streams and ponds
• The best drainage rock due to its large void spaces between each rock

Cons

• Will not compact and provide stable footing
• Hard to shovel by hand
• Can look dirty over time when compared to clear material

Typical Uses

River rock is typically used in a decorative setting, or when the best drainage material is needed. It provides a very natural look around water features, as is has already been worn smooth by nature.

Color

As with any natural resource product colors will vary. The two main color sources though are round rock and river rock.

Just like the name implies round rock is rock that has been dug out of the ground, separated from the soil, and in most cases put through a washer. It usually has a light brown tinge to it.

River rock is dredge from a river bottom. It typically has a few blue colors in it, and is much brighter.

Typically speaking a decorative rock should be river rock, while a French Drainage rock could be round rock because the drain is buried underground and the color of the rock does not matter.

Things To Consider

If you are looking for a certain color of rock for your project, your contractor may ask you to go to a landscaping centre and look at what is available before purchasing materials. When rock comes from the quarry, there is no guarantee what color rock you will get. This is because the rock is coming from the mountain, and each section of the mountain can contain different colors. So, in essence, you could get a load of gravel that is bluish in color, and a second load that looks browner in color.

If color is important to you, look at what material you are getting before purchasing. If you do not care what color your gravel is, you will benefit from getting the gravel straight from the quarry, as it is more affordable.

Another thing to keep in mind when purchasing gravel is that the quantity of rock that you receive is going to be different depending on where you get the material from. At landscape centers your gravel is loaded with a small bucket, and is measured by volume called cubic yards. This is relatively accurate as a full bucket cannot be overfilled.

At a quarry, a large machine will be loading the gravel, and the material is measured in tonnes.

The bigger the machine that is loading the material, the less accurate the measurement will be. You may ask for six tonnes at the quarry and end up getting five or seven tonnes. Remember, that if you receive more material than needed you will need to find somewhere else to put it, or have the material hauled away. If you run short of the materials you need, you may have to get more. Both options will result in extra costs/ hassle that you may not thought of.

There are lots of gravel options when it comes to giving your property an upgrade. By choosing the right type of gravel for what you are looking to have done, you can be sure that you will reap the benefits of gravel. With its ease of installation and low maintenance (you may need gravel touch ups here and there every year) it is a great product to use for your landscaping needs.

Curious about the cost of gravel?