The Best Landscaping Stones for Your Water Feature

Landscaping is a fun and sometimes intimidating part of designing a pond. Adding the right pond rocks and stones can make a water feature look natural and organic. Waterfalls and fountains are more captivating when they seamlessly integrate with nature. Little tricks like hiding cords and pumps and using stones that complement each other can influence the overall look. 

This quick geology lesson will help you learn the different types of stones to see their place in landscaping. There are three rock groups: sedimentary, metamorphic, and igneous, categorized by how they form. 

Sedimentary Rocks: Limestone and Sandstone

Sedimentary rocks are composed of layers of sand, shells, fossils, and other "sediment." The layers are sometimes visible. These rocks are the softest and often most porous. When used in water features, these rocks absorb some water and often become grimy.

Porous rocks can be problematic outdoors in places with freezing temperatures. They can crack as the water freezes and thaws. You can use porous rocks indoors or in areas with less rain and hotter climates like Arizona. 

Limestone can be worn down by water or easily broken. This type of rock in your pond can cause the pH and water hardness levels to rise. The added minerals can also promote algae growth. 

Sandstone is often used as a stepping stone because it is easier to cut and carve and less absorbent than limestone. You can treat and seal limestone and sandstone to be less porous. Both stones come in many colors and look very natural.  

Metamorphic: Marble and Slate

Metamorphic rock started as igneous or sedimentary rock and then transformed through heat or pressure. These rocks are harder and more durable than sedimentary rocks. Marble is famous for its historical use in Greek and Roman times. Today it's still used for fountains, waterfalls, and other structures but is more expensive than slate or granite. Marble chips are a commonly used larger gravel substitute. 

Slate is a popular stone to use around the edge of the pond. It is a strong stone that is not affected by freezing and thawing. You can use slate in different outdoor projects, and it's available in many different colors. Slate stones are often larger and thinner and can be stacked well to create a waterfall.  

Igneous Rocks: Lava Rock and Granite

Igneous rocks form by lava cooling and solidifying. Lava rock is rough and is not the best choice to use inside a pond with fish. Fish can scrape against the rocks and lose scales. Granite is great for water features because it is hard and not porous so it will need less maintenance. 

Depending on where you live, you may have the option of unique regional stones, which may be more affordable and easier to find a supplier for. Some regions in the US have natural granite, while others have sandstone or limestone. Pennsylvania, for example, has natural mica. These stones are blue-grey and are great for use around the pond's border.   

River Rocks

River rocks are the traditional "pond rocks" found in a river or stream in nature. The water's current rounds river rocks over many years. They come in different sizes, and their mismatched shapes give them an elemental quality. You can use the larger stones around the pond, while the smaller rocks are great for pathways or decorative accents. 

River rocks have a naturally smooth finish and look lovely with water flowing over them. You can use river rocks in bubbling fountains or container fountains. The smooth surface makes a wonderful sound when the water hits it. They're an excellent choice for stream beds. Small river rocks are called pebbles and are a popular gravel alternative

Gravel

Gravel can be a combination of many different rocks, from granite to limestone. Gravel is harder to clean than river rocks, so it's not recommended to use in the pond. You can use gravel around rocks, pavers, and bigger rocks instead of mulch.  

Flat Rocks

You can place flat rocks around the pond in a single layer or stack them together to add depth and texture. These rocks are great for turtles, frogs, and other creatures to sunbathe and absorb the warmth. When using flat rocks that will be stepped on, make sure they are not too smooth, or they will become slippery when wet. If their edges are too jagged, people and animals can get hurt, and the pond liner can rip. 

Rock Sizes

Large boulders and rocks can create a nice place to sit and enjoy your pond. Stones and rocks help keep the pond liner in place and create a barrier. Typically the larger rocks help hold the liner down, and then the smaller rocks are integrated as decoration. Larger rocks are harder to transport and move around. Smaller stones are easier to install but are less sturdy, which can be problematic if they are on a walking path.

Waterfall

Waterfalls are beautiful additions to a pond. You can choose to make a large waterfall, with multiple levels and a stream, or a smaller waterfall, just using rocks to hide the spillway. Large flat stones are a popular choice to build a waterfall. You can stack flat rocks on top of each other, so the water can flow, hitting the lip of each rock as it goes down. When building a water feature, like a waterfall, the bigger rocks are sturdier and can be used as the foundation, creating the infrastructure, while the smaller rocks are accents to complete the design.  

You can easily build a waterfall using the smartpond 8-in Spillway and then cover the spillway with rocks and plants so it looks natural. 

Rock Design

In nature, there is often a "main" type of rock in a stream or waterfall, with some other kinds of rocks occasionally seen. If you want your water feature to look natural, choose one main type of rock for the feature and complementing rocks as accents. All of the rocks should follow a similar color scheme. They do not need to be the same exact color, but all similar shades of red, grey, etc. Stones in nature are not the same size or shape.

Pavers

Pavers can be made of natural stone or made of brick and concrete. You can them as a border for a pond or water feature. Depending on the design, they can look like natural stones, compiled of different shapes, sizes, and color variants, or they can be uniform for a contemporary look.  

Faux Rock

Faux rocks can be made of fiberglass, plaster, or fiber-reinforced concrete. It can be mixed and molded on-site. Faux rock is great if you're looking for a custom look or are not able to transport the rocks to your pond. Some faux rocks look extremely realistic, with different shapes, colors, and textures that look like real stones. 

Choosing the right landscaping stones for your water feature and pond can help make it look organic, as if it was created by nature and always there. Some stones are better suited for water features, while some should stay indoors. You can choose regional stones to reduce costs or have a custom faux rock made in your own backyard. There are many design options to choose from when designing your pond and water features, let your creativity flow!