It’s the kind of project landscapers dream of: a solid referral, an unlimited budget and a client willing to let the design/build team have its way.

Bismarck is booming. While other cities around the country are struggling to pay the bills, North Dakota’s capital city is more than holding its own. Thanks in part to the rapid growth of oil exploration to the west and the state’s astonishing unemployment rate – at 3.1 percent, it’s the lowest in the nation – it’s no wonder the city is growing. The metro area’s population has increased nearly 6 percent in the past two years alone, resulting in new building and the desire to improve existing homesteads.

Situated on the banks of the Missouri River, Bismarck’s land ranges from gently rolling to steep incline, where landscaping becomes a challenge. Just north of downtown there’s a home where landscape professional Cody Wilhelm was given the opportunity to tackle such a slope – and where he created a sunset haven the homeowners love.

At Dakota Impression’s dream job site, an couple of existing rock walls were salvaged to provide material for the natural-looking waterfall that now graces this sloping North Dakota property.
Photos courtesy of Dakota Impressions

Blank slate

The job came as a referral from a previous client who’d been pleased with the work Dakota Impressions Landscaping and Design LLC had performed on her own property. “[The homeowner] got me out on site and asked, ‘What can we do?'” Wilhelm explains. “I told him we could do a lot of different things, and he said, ‘Draw me something up, give me a price, and give me a wow factor.’ We really didn’t have any restrictions, or anything that would prevent us from doing whatever we really wanted, so it was kind of a blank slate.

“There wasn’t a budget,” Wilhelm continues. “He didn’t put a price tag on anything. He said, ‘Don’t even worry about what it’s going to cost; I want you to design me something, let’s go over it, and shoot me a price on it.’ [He] obviously wanted to okay everything, but he was pretty open to letting me use my creativity. He figured, ‘Let me see what this kid can do, and then if we need to tweak it a little bit, we can.’ And after I proposed the plan, we didn’t change a single bit. He just fell in love with it. We added a couple of small things, like some pathways, but other than that it was pretty much, ‘yeah, we love it, let’s do it.'”

Who wouldn’t love a client like that?

Backyards in this relatively upscale development tend to be unusable for all but sledding, but they come with a distinct advantage. Open land behind the properties was purchased by homeowners and donated to the Bismarck Parks and Recreation Department, expanding the open space and essentially guaranteeing that the vista would never change. “That [donated] land can never be developed, so they won’t have other houses in their back yards. The view overlooks a good portion of north Bismarck,” Wilhelm says, “and you can see the [Missouri] river from the top of their property.”

And sunsets? More entertaining than video on demand.

The plans

The nearly 1-acre site contained a relatively small pair of existing retaining walls cobbled together from boulders, with railroad-tie steps leading from one tier to the next. Below that, the property sloped away to borrowed vista. The original installation provided a bit of flat area, but it proved to be uninviting and was seldom used.

The massive boulder to the left of the waterfall was upended to create a natural transition from segmented wall to water feature. Block was meticulously cut to ensure a seamless fit.

What Wilhelm saw was the potential of the property to offer the homeowners a refuge where they could entertain guests or simply escape the everyday hustle. “Basically, the whole point of the project was to create a space where they could sit out and enjoy their view – that wasn’t from the top of their deck – to help them feel they were someplace else,” he says.

The design called for new walls, a number of tiers that provide patio areas connected by meandering paths, permanent seating surrounding a fire pit, and new plantings to tie the grassy slope to the surrounding environment.

Replacing the retaining walls was a given, but Wilhelm immediately saw that the site was perfect for a sizeable water feature. This would serve both to break up the massive walls necessary to hold the slope and to provide a focal point on the property. “And, obviously, it added that wow factor,” Wilhelm says. “When you step out back, you don’t even feel like you’re in somebody’s back yard; you feel like you’re out somewhere.”

Backstage access

Considering the difficult grade of the property, Dakota Impressions crews quickly discovered the challenge of using existing equipment on a steep grade. “The property proved to be a lot steeper than it looked when we bid,” Wilhelm explains, “and we weren’t able to use our skid steer machine; we couldn’t get up and down the hill with it. So we had to buy a track machine especially for this project. We struggled with trying to build those retaining walls on those hills, and how we were going to get the blocks to where we needed them without them falling down the hill constantly.”

The new track skid steer allowed the crew to store materials at the bottom of the hill and move them upslope easily. “On slopes, the track machine allows you to be more stable; it doesn’t want to tip as easy,” Wilhelm explains. “It also helps with not tearing up too much; you’ve got less pounds of pressure per square inch on the track than you do with the wheeled machine. You don’t sink in when you’re turning.

“That’s all I use right now, is track machines. I got rid of both of my wheeled machines.”

Some of the material was already on site: The crew made good use of the existing boulders by incorporating them into the water feature. “We tore up the existing walls and reused all that retaining wall rock, which we installed around the water feature. So we probably only hauled in around 26 tons of rock,” Wilhelm explains. The remaining imported material then was limited to the block and cap used for the retaining walls, fieldstone pavers for pathways, plus mulch. This was staged at the bottom of the property and transported uphill as needed.

Two 4-foot slate slabs form a footbridge, inviting visitors to cross the water feature on their way from the house to a large patio on a lower tier.

Building the wall

Retaining walls always pose a challenge; proper stabilization is critical no matter where the structure is installed. But Wilhelm and his crew added to the puzzle by selecting a retaining wall system they had never used. Wilhelm selected the Rockwood Vintage system, specified through Rochester Concrete Products, “because it gave us six different sizes, so it was a more randomized design,” Wilhelm says. “It was kind of a challenge for us, to use a block that we weren’t yet comfortable with, but we then used the same block to build the staircase.”

Because the top of the block has an unfinished look, the crew installed a charcoal cap: “The block is in Santa Fe colors,” Wilhelm describes, “and then we used the straight charcoal cap just to give a nice, dark accent. I thought it made the walls pop. It kind of defines it more than using the same color cap as the wall; it offsets it a bit, and the cap is what gives you a finished look on the wall.”

The charcoal cap also was used to create the steps, highlighting the buff-colored risers and allowing the contrast to provide a kind of safety feature. “The other safety feature we added is bracket light fixtures that shine down and light up the staircase at night. There also are fixtures that light up the pathways, plus there are lights in the water feature that light up the falls.”

A large patio area was created behind the top wall and includes a fire pit and a permanent seat wall. “The fire pit area is where you go to sit and enjoy the sunset. [The homeowners] have a perfect view of the western side. They can sit out there and listen to the water flow, enjoy the sound of that, watch the sunset,” Wilhelm says. “The fire pit’s just a little added feature. They’re not going to go down there to eat because it’s too far away from the house; it’s one of those areas where they go down there to get away. It’s something they’re going to use more in the evenings, to relax after a good day of work or whatever the case may be. The little seating wall was installed so that they wouldn’t have to drag chairs down there all the time.”

For the patio surface, “we used Rochester fieldstone pavers,” Wilhelm explains, “because we wanted it to look as natural as possible, but we didn’t want to use slate – because slate’s not perfectly level, and you always end up finding a crack with your chair when you’re sitting down. We used the fieldstone paver because it looks like a flagstone. Then we tied that into the flagstone walkway, and that leads through the mulch bed to the staircase and the water feature. We placed two big, 4-foot pieces of slate to make a footbridge that spans the water, so you actually walk across the water feature to get to the patio area.”

Everything “kind of steps down,” Wilhelm describes. “Most of the outdoor living space is below the tiers, so it’s kind of sunken into the hill. But you still have an amazing view overlooking Bismarck, with open land below.”

The fiery foliage of a Sienna Glen maple echoes the hue of the tinted mulch, used to draw attention to various elements of the sloped landscape installation.

Falling waters

The highlight of the backyard installation is the water feature, which bisects the new walls. It was installed using materials from EasyPro Pond Products and “recycled” boulders from the original retaining walls. It’s a pondless waterfall that tumbles gracefully from the upper patio tier, under a slate bridge, down a final 8-foot drop and into a 10-foot by 12-foot basin that contains up to 15,000 gallons of water. The basin is approximately 5 feet deep, but it’s filled with blocks that are topped with rocks, creating a false elevation. “You don’t have the maintenance of a pond,” Wilhelm explains, “and the pump is buried below the water. It’s a 220-volt pump that circulates 14,400 gallons per hour, so there’s quite a bit of flow going through there.”

Water is constantly recirculating with the help of a 3-inch exchange line, through the buried tank. “There’s a check valve on that 3-inch line that maintains the line to stay full – and the tank to stay full – so you don’t have to fill it up every time you turn it on or turn it off,” Wilhelm says. “There’s always water in there, unless it’s shut down for the winter, so it doesn’t take as much water to fill the feature.”

The homeowners are “into entertaining guests, and they like to sit outside to enjoy the view as well as the sound of the water,” Wilhelm says. “Even from the top of the deck or from inside the house, if they open the windows they can hear the water feature.”

Blending elements

Tying together the segmented wall with the natural boulders of the water feature posed a unique challenge, but Wilhelm was determined to find a way to create a seamless transition. Because the waterfall appears to burst forth between sections of the wall, blocks and boulders needed to blend almost naturally.

“Once we got into [building the wall], I was thinking, ‘how am I going to transition from block to water feature? How do I make this transition and make it not look weird?’ We didn’t want to do anything like a pillar or something with the block. I wanted it to flow naturally and tie into what the water feature was going to give us,” Wilhelm recalls.

One particularly large boulder was recovered from the original retaining wall, and when Wilhelm spotted it, he knew what to do: “I thought, if I stand that thing up, I can just run my block right into it, and that’s a great way to end one piece and start another piece. We built the retaining wall, then we stacked the rocks up there and attached the retaining wall to the rock.” The boulder was placed upright at the end of one wall segment, and “there was a lot of meticulous cutting along that rock to get that block to fit in there,” he explains. When the fit was secure, the crew continued the practice of intricately placing smaller boulders at the block intersections to give the appearance of natural falls spilling over a manmade wall.

The view from the fire pit patio takes in some of North Dakota’s spectacular sunsets.

Add some color

Rock beds were replaced with colored wood mulch; according to Wilhelm, the homeowners had “hated” the original rock beds. “The problem with the rocks is after about four or five years, after dirt and debris blow in there and it all breaks down, you end up getting weeds,” Wilhelm explains. “Once the weeds start growing, you can’t get them out of there unless you rip out all of the rock and replace it. So the homeowners wanted wood mulch.”

Wilhelm chose red mulch to provide a pop of color and to contrast with the tan of the retaining wall and the charcoal caps. “Red is really an eye-catcher. They say red is the most common color used in advertising because it draws people’s attention the most. That’s why I went with the red color; to draw people’s attention to the features,” he says.

Plants were selected for a native look and feel. “We used some Ponderosa pine trees to anchor on the sides; we chose those because they’re kind of an airy tree, but they’re year-round color,” Wilhelm says. “The nice thing about them is they don’t kill everything on the ground underneath them. They’re up off the ground and you can see through them; they’re not as dense as other evergreens.”

A Sienna Glen maple provides shade and height, plus a blaze of color in autumn. Dwarf evergreens, including a few weeping white spruces and a hillside Scots pine, dot the installation. “We used a lot of specialty evergreens that we get out of Oregon, from Iseli,” Wilhelm says. “And then with those evergreens we tied in some Russian sage and some native grasses. We did some potentilla to give us a splash of yellow color; it kind of gave us that native look. We did some yellow and purple coneflowers, and we chose some creeping juniper to give a nice groundcover in some of those bigger mulch areas. We tried to use the biggest plants possible to provide that sense of instant gratification.”

Dakota Impressions

Dakota Impressions Landscaping and Design LLC, based in Bismarck, N.D., is relatively new; established in 2010, this is only its fourth year in business. But owner Cody Wilhelm has plenty of experience in the landscape business, starting as a laborer when he was in high school and moving up the ranks to project manager and eventually owner of his own company.

“I started landscaping when I was about 16 or 17 … it was a great job when I was going to school and going through college,” Wilhelm explains. “It was pretty flexible. I enjoyed working outside, working with my hands. I grew up on a farm, and just couldn’t see myself sitting at a desk all day.

“I started out as a laborer, went to being a foreman and then went into sales and design. Then my last couple of years I was a project manager and I oversaw the crews. As I did the design I also managed the crews on top of it.”

He continued working in landscaping all through college, he says, maintaining a 40-hour workweek while studying full time. He earned a business degree with a minor in management, which has served him well as a business owner. “The business degree helped,” he says, “but the most valuable thing was working for other people and seeing how they run their businesses; taking away the good and the bad and trying to learn from their mistakes and trying to learn from the things they were doing right. Getting that project manager position and managing four or five crews for a couple years really gave me the experience I felt I needed to finally break away and do my own thing. The classroom stuff is great – it’s stuff that you need to know – but I think the hands-on experience is where you really get the knowledge that you need.”

In the first year at the helm of his own company, Wilhelm expected Dakota Impressions to function successfully with one crew. “But I filled so much work I decided to have two crews right off the bat. And now we run four crews and employ 15 employees.”

The project took about nine weeks to complete with a crew of four. And although it looks like it’s sprouted naturally from the North Dakota slope, the installation was completed in 2011. That same year, Wilhelm submitted his work to the North Dakota Nursery and Greenhouse Association’s competition for backyard design, where it garnered first place recognition.

The homeowners? “We never had one complaint, Wilhelm states. “It was a joy working for them; they were just the model clients. They didn’t want to restrict me in any way, they just wanted me to be able to use my creativity and create something nice for them. They’re 100 percent happy.”

Sally Benson is editorial director for American Nurseryman. She can be reached at Visit Dakota Impressions Landscaping and Design LLC at