Are Rocks Better Than Mulch?

Homeowners longing for a better-looking garden bed are bound to look for ways to cover the ground. Choices can include a variety of rocks, stones, or mulch. So many choices can make it confusing to decide which one to buy. 

Are rocks better than mulch? Advantages and disadvantages exist with each option. Rocks are more expensive than mulch but don’t need to be replaced as often. They are also a great option for weed and insect control. Mulch offers nutrients to the soil and doesn’t retain the heat that rocks do. They also don’t compact the soil as rocks or stones do. 

The article below offers some information that can help you decide if you rather have rocks or mulch. 

Varieties of Rocks

Rocks or stones can be as decorative as mulch as a ground cover. They come in many sizes, shapes, colors, and textures so they can add variety. 


Types of rocks to choose from include decomposed granite, which is common gravel. More than 30 colors are available in landscaping gravel. It can be a rough or crushed stone. 

Natural decomposed granite is a non-processed stone that works well in barren areas where plants don’t grow well. 

Decomposed granite with resin is a natural-looking asphalt that is permeable. It’s easy to install and remove and can withstand high traffic.  Decomposed granite with a stabilizer is used for pathways and patios. It forms a solid, easy-to-maintain surface. 

Read: How To Get Rid Of Mushrooms In Mulch?

Pea Gravel

Pea gravel is a type of river rock that is rounded and smooth. It is small and comes in natural colors. However, unlike the crushed granite, pea gravel doesn’t stay in place. It can blow or roll so you shouldn’t use it on slopes or an area without a boundary.

Read: What Is Mulching And Its Advantages?

River Rock

River rock is bigger and rougher than pea gravel. This makes for a good foundation for many landscape designs. River rock stones are wildly different whereas pea gravel is more consistent in shape and size. 

There is also volcanic rock, glass rocks, and other forms of pebbles. 


Mulch comes in different varieties also. There is cedar, cypress, pine bark or chips, straw, and compost. The wood chips come in several different colors but the most popular are black and brown. 

Organic mulch adds a more natural, casual tone to your flower beds. They will need to be replaced more regularly than rocks but add nutrients to the soil as they decompose.

Read: How To Attract Deer To Your Yard?

Rock Advantages and Disadvantages

Some of the biggest advantages of using rocks or stones instead of mulch are it is extremely low maintenance. It is the right choice for controlling weeds and fungi. Rocks prevent erosion and provide good drainage so they are good to use in areas where you have pooling water.

Rocks and stones work well to create dry creekbeds too, which can help with drainage as well as add a landscaping feature to your yard. 

Rocks also reduce water from evaporating from the soil, so more water goes to the roots. 

The disadvantages of rocks are that they don’t break down so they don’t provide any nutrients to the soil. They can be heavy and difficult to install, cost six times more than mulch, and can compact the soil.

Soil compaction is a serious issue because it could prevent the growth of other plants you may want to plant later.

Rocks will eventually move into the soil so some will disappear after a few years. You may need to dig those out to refresh your flower beds and prevent rocks from getting so buried they ruin the soil.

Read: What Is The Cheapest Way To Landscape A Backyard?

Mulch Advantages and Disadvantages

Mulch is easy to work within the installation and is cheaper than rock. It can help trees and plants grow taller faster, retains water that plants absorb, and regulates the temperature of the soil. Mulches also control weeds and decompose so they keep soil healthy. 

You don’t have to remove mulch to replenish it. You can just top off old mulch with new mulch, making it easy to maintain once it’s installed.

Mulch works well in both shade and sun. It doesn’t hurt plants as long as you install it correctly, although it can suffocate plants if layered too deep around them. Mulch around trees helps double their growth.

Disadvantages of mulch include that it requires more maintenance. You must rake it after heavy rains and replenish it annually. It can be washed away with rain and wind. Mulch can attract insects including ants, cockroaches, and worms. It can also be a fire hazard. It loses its color after months or a year, depending on the mulch.

When to Use Rocks or Mulch?

The two types of ground coverings aren’t interchangeable. Rock or stone can hurt some plants and mulch isn’t effective in all cases. 

Rocks work best in areas where plants or grass won’t grow, rock gardens, or around flammable areas like fire pits. Rocks and stones don’t work so well in areas of the direct sun because they can get hot. They also shouldn’t be used around trees or plants with fragile roots or stems.

Mulch works best in areas where there are delicate flowers, around trees, and places where there is full-sun exposure. Mulch can be used around flowers or vegetable gardens. 

The choice of using rock or mulch depends, in part, on your personal preference, the landscape design, and the plants you are working within the beds.

Read: How Do You Build A Simple Backyard?


Are lava rocks cheaper than mulch?

Although there are different prices for various types of rocks, rocks or stones always cost more than mulch. Generally, they can cost two to six times more than mulch depending on the rock. 

Can you put mulch over rock?

It isn’t the best way to handle landscaping as some designers say you must take out all the previous products if you completely change products. Yet, others said you can put mulch on top of rock because rocks continue to offer a good foundation although they don’t benefit plants as mulch does. 

Will bugs live in rocks?

Bugs could live in rocks but tend to pick larger rocks that have more spaces between them. Small stones are excellent as a natural insect deterrent. 

Which is better at preventing weeds, rocks, or mulch?

Rocks are better at successfully preventing weeds than mulch. They are heavier and don’t decompose. 

Do rocks hurt plants?

It doesn’t hurt them but offers no benefit to plants. That’s because rocks don’t provide any nutrients to the soil surrounding plants and trees. Rocks can hurt trees because trees need acidic soil and rocks create soil with alkaline. 

How do you install rock mulch?

Dig the area to install landscape fabric. Place rocks in the sun and wash them with the garden hose to get old dirt off. Let the rocks dry completely before putting them in the flower bed. Don’t put more than two inches of rock or stone down.

How do I clean my rock bed clean?

The easiest way to keep a rock bed clean is to occasionally spray them down. Choose a spray setting that doesn’t move the rocks and doesn’t overspray the area. You’ll want a setting that rinses off dirt without displacing the rock.

Rocks and stones should only be cleaned if they get muddy or dirty. Otherwise, they don’t require maintenance.