Mulching your garden beds with rocks comes with a lot of benefits. Rocks do not need to be replaced every year like wood mulch or pine needle mulch. Their weight makes them very effective at thwarting weed growth, and they look very tidy. But once you decide to mulch your garden beds with stone, you have to decide what type of stone to use. Here are some of the best types of landscaping rocks for the job.

River Rocks

River rocks are rocks that have been pulled out of, quite literally, a river. After years of being tossed around in the rushing river water, these stones tend to be really smooth on all sides. Some are sort of flat, while others are rounder. Think of the type of stone you would find on a beach and skip; those are river rocks. There are a variety of types of rock in the river rock mixtures a landscaping company will deliver. The variation in color looks lovely in most landscapes. Since most river rocks are reasonably small, they are easy to move and put into your garden beds — good news if you're moving your own rocks by hand.

Lava Rock

Lava rock, as the name suggests, is rock that has been formed from molten lava that cooled and solidified. This rock is harvested from volcanic sites and transported to the places where it is needed. So, it can be quite costly if you don't live near a volcanic site and cheap if you do. Lava rock is pretty lightweight because it has a lot of air worked into it. This makes it easy to move into garden beds. It usually has a reddish rust color, which looks lovely in some yards and not-so-lovely in others.


Limestone is a hard rock with a medium to light gray color. You can buy it in various sizes, but for garden beds, you usually want a fairly coarse limestone. This rock has a lot of texture and adds a lot of interest to a yard, and yet its neutral color makes it a good choice for any landscaping design. Limestone is also very affordable compared to other types of landscaping rock, although it is heavy to move.

Any one of these types of rocks would be a great choice for most gardens. For more information, contact a local landscaping business that offers a variety of rocks, like Portland Sand & Gravel Co Inc.