How does rock do it all? Let’s take a look.

Benefits of Rock in Your Pond

Different sizes of rock work together to give a pond its form. Medium to large boulders provide an attractive perimeter and define the shelves and ledges around and inside the feature. Gravel at the bottom of a pond protects the pond liner from foreign objects and the sun’s UV rays. Rock holds the pond liner in place, keeps the ground from shifting, and offers firm footing. Ever tried walking on a bare pond liner? It’s like a Slip ’n Slide!

Small rocks and gravel also help lock bigger stones into place. They eliminate gaps that could cause the stones to shift over time. Your best bet is to use gravel that’s smooth and round. Avoid any varieties with jagged, pointy edges – they can damage your liner.

Let’s face it: the problem with rock is that it’s heavy and difficult to move. That’s why many DIYers are tempted to skimp or even skip some kinds of rock. But each size of rock performs an important structural task. And all of them are necessary to construct a pond foundation that will stand the test of time.

Beneficial bacteria live throughout the rocks and gravel of a pond. They help keep the water clear by consuming excess nutrients and breaking down organic debris. Basically, these bacteria eat up the fish waste and stuff like leaves and grass clippings that fall to the bottom of the pond.

Without the gravel at the bottom of a pond, bacteria would have nowhere to live … and without constant maintenance, the gunk would just build up. A pond with a stable ecosystem of biological filtration, mechanical filtration, rocks, fish, and plants will sustain a healthy balance and clear water.

At Good Earth Water Gardens, we believe that ponds can be a vital part of the landscape and look like they’ve been there forever. That’s where the aesthetic element of rock comes in. While some pond enthusiasts may disagree about using stone and gravel to cover a pond liner, we think it looks more natural than a black liner that has the Firestone logo printed on it.

The right boulders and edge rocks can create a habitat that looks like the pond developed naturally, especially in an area like a waterfall. Look at photos from national parks to get an idea of how rock formations naturally occur around bodies of water. You’ll see how larger “frame rocks” are usually located each side of a waterfall, while the water cuts through the middle on a lower stone. We use the same principle when building our features. Keep in mind that boulders, while tough to transport, are crucial to a well-designed water feature.