Boulders are a fundamental landscape element in the designer’s repertoire. We’ll discuss the principles of their use in the home landscape, fitting them into a garden composition, and how to physically integrate and install them in their new surroundings

If you’ve considered incorporating a large decorative stone into your beautiful garden to make it even more beautiful, you are not alone. Other than plants themselves, boulders are becoming one of the most popular ways to introduce timeless four-season interest into a home landscape.

What’s behind this popularity? For many of us, rocks have a symbolic, almost archetypal meaning. For ages, they were considered one of the fundamental elements of nature, long before science came along and gave us the periodic table. They are symbols of stability, endurance, and timelessness, persevering against the very forces of nature.

They suggest age, speaking of it in terms of eons compared to our fleeting human existences, making our landscapes look much older than they actually are.

There’s no doubt, boulders are a fundamental landscape element in the designer’s repertoire. With that in mind, this article will discuss the principles of their use in the home landscape, how to fit them into a garden composition, and how to physically integrate and install them in their new surroundings.

There’s a right way and a wrong way, and we’re going to set you down the true path to happiness and contentment!

For Those About to Rock

Before you commit to bringing a boulder into your landscape, you should first be certain of your motivations for wanting a boulder in your yard. Too many people decide on the spur of the moment to put a large prominent rock in their garden without having a particular purpose in mind, and end up with a sore thumb mocking them for eternity.

Know why you’re introducing a boulder into your landscape, and make sure it’s a reason beyond simply “I want one” or “I like the way it looks”.

Boulders can be used in the garden for purely functional considerations. They can give topographical relief to a composition, forming a prominent and enduring vertical element. They bring a certain ruggedness and steadfastness that contrasts well with the natural softness and dynamics of plants.

A strategically placed boulder can create a micro-environment for plants in its midst, providing managed shade, retaining heat in winter, or simulating specific alpine conditions. An appropriately shaped boulder could even be strategically placed along a garden path to be used for sitting.

Your objective might be to draw inspiration from a natural rock setting or remote landscape that has caught your fancy and recreate some of that in your garden. It could be a craggy mountain path you once hiked, a natural boulder in a meadow you recall running across as a child, or a rugged boreal outcropping on which you pitched your tent on a recent camping trip.

You’re not trying to literally rebuild the scene from memory, but rather to borrow the aesthetics of this natural setting and fit some of them into your smaller home landscape scale.

Boulders are an important element in many specific landscaping styles; the southwestern dryland motif or desert scene, a Rocky Mountain vista, or a Japanese garden concept. Of particular interest, Japanese design theory suggests the importance of their placement relative to the composition, taking a “microcosm approach” by creating a small version of a grander landscape in your yard.

Here the boulder might literally simulate a scaled version of a mountain amid forests of plants or an island adrift in a sea of manicured sand or gravel.

Feature rocks add enduring interest to a garden

In Search of the Perfect Boulder

Your ideal boulder should be defined in part by its role in your landscape composition. If you are recreating a specific natural environment, the boulder should be similar to those found in that environment. If you are borrowing elements of a specific style, the boulder should be suggestive of that style. If the boulder is simulating a grander landscape feature, it should resemble that feature on a smaller scale.

In general, a feature rock should be evaluated in accordance with the basic landscape design principles of shape, color, and texture; consider each in your selection. The shape is particularly noteworthy, affording the opportunity for a boulder with a meaningful vertical component to play a role in your winter landscape scene as well.

You will want to look for distinctive or unique features that create interest and draw the eye. Rather than looking for oddities or anomalies, look for features that are in harmony with the purpose of this stone in your composition. Seek those which suggest timelessness, permanence, and substance.

It is critically important that your boulder is of an appropriate scale relative to your garden, your landscape, and your home. If it’s too big, it will draw attention away from the home and the other features of your landscape, ultimately making it stand out like the proverbial sore thumb.

Too small, and it will slip past the eyes of your would-be admirers, and once seen, appear as more of a poor afterthought than an enduring fixture in your landscape. A good rule of thumb would be to keep the rock between 2 and 6 feet in diameter, with a smaller rock for a small yard and garden, and the largest for an estate-scale composition.

A word is in order here regarding so-called “artificial boulders” versus the genuine article. There are certainly advantages to these man-made surrogates; because they weigh significantly less than their natural counterparts they are far easier to transport and set in place, and they are also significantly cheaper.

However, the disadvantages are not insignificant. Artificial boulders have a limited lifespan, they readily show wear and tear and certainly don’t weather “naturally”, and too many of the cheap rip-offs look, well, cheap. When it comes to appearance in your landscape, nothing beats the real deal.

Integrating Boulders Into Your Garden

Unless you specifically want your boulder to stand out like a sheep at a wolf’s convention, you’re best to consider the selection and placement of your boulder in the context of the overall composition, ideally both that of your garden and your entire landscape. In this context, your boulder will almost always serve as an accent or focal point, drawing the eye and creating interest.

As such, it should be thought of as an accent in the landscape sense, meaning less is more. Frankly, most suburban landscapes can only support one or perhaps a couple of boulders before they become ubiquitous and lose their uniqueness and appeal. For maximum effect, use only one primary boulder in any given garden.

In order to not look out of place, your boulder will need to be situated in conjunction with one or more elements that tie it to the rest of your composition in a natural way. You could supplement it with a couple of smaller stones placed strategically nearby, but they should not upstage your feature rock.

You may use continuity to integrate your boulder into the composition, for example by surrounding it with smaller rocks of a similar type, embedding it in a gravel mulch or sand bed, or sitting it in a decorative rock stream bed.

Of course, plants are an important way to tie them into your garden. Complement the colors of the stone in your selection of plants, seeking colors that reflect those in the rock as well as those which contrast it. Use low-growing facer plants to surround the base and anchor the boulder to the ground.

Leverage trailing plants such as junipers and creeping jenny or rambling, climbing plants like Virginia creeper or climber roses on the upside of the boulder to flow around and over it. Don’t worry about partially concealing parts of your boulder; this will only help to further integrate it into your composition.

Remember that in nature, rocks don’t mysteriously appear in the middle of a level manicured bed of soil, so pay close attention to how the base of your stone is set into the garden. Bury as much as a third of your rock into the ground, such as to only have tapering angles above the ground, as you would find in most naturally occurring outcroppings.

Generally, smoother stones would be buried deeper in keeping with the sense of sustained erosion they should convey, while stones with more jagged reliefs can be set higher in the ground. Whatever you do, don’t just plunk the stone atop the grass or soil; nothing will look more artificial right off the hop.



A Stone’s Throw to Your Yard

Put some serious thought and effort into preparing the final resting place for your boulder. It should only be sited in a proper garden; besides looking contrived, placing it directly in turf grass will rapidly degenerate into a long-term maintenance nightmare.

Be careful that it will not be located on a slope where it may roll and present a serious hazard. If it is to be used on a slope, you’re advised to consult with a landscape architect or civil engineer for advice on securing the stone such that this hazard is eliminated.

Study your rock long before it makes its way into your garden. Determine which end will be buried, and then estimate the depth to which it should be buried. Dig an appropriate receiving hole in the garden for your boulder, filling in with a little crushed rock underneath to facilitate drainage and prevent shifting.

Also, note which side of the boulder will face which direction once in place. Identify the “best” or most interesting face of the rock, and then determine from which vantage point you want this to be seen.

Most often this will either be from a public viewing point such as a sidewalk or road, or from a well-traveled pathway or driveway on your property. Identify this side and mark it with sticky tape, because it will be the last thing on your mind when you’re in the process of actually placing this behemoth.

The greatest challenge will be moving your rock into place. Whatever you do, don’t underestimate this! Average “home-scale” boulders can range in weight from a hundred pounds to a thousand pounds or more, and unless you’re into serious bodybuilding with copious supplements of steroids, there’s no way you’re going to be moving this yourself.

If you’re purchasing it from a garden center, landscape supply store, or quarry, ask whether they can transport it to your place, and ask about their ability to actually drop it in place in your garden. If you’re hauling it yourself, save your back and give serious consideration to hiring someone with the proper tools to do this.

And one final note, get the location right the first time! Unlike shrubs and perennials, once in place and in its hole, you’re not going to be relocating this boulder any time soon.