Why did this paver walk fail? The value of edge restraint

failed edge paver walk

I was walking into a meeting at a hotel last week when I saw what my path looked like. Here’s a hint: your paver walk should NEVER look like a half-unzipped Members Only jacket. How did this happen? Improper edge restraint. To explain, let’s step back and look at how a paver walkway should be installed.


Keeping it quick and dirty, you excavate to undisturbed soil and build back up with a base of compacted 21A (3/4″ minus gravel). As in the sketch I did, you extend the base past the edge of where the walk will go. You then use a paver edge restraint spiked into the compacted base. Two things caused the walkway in the photo to fail: they clearly did not extend the base far enough, and they did not use proper edge restraint. It’s a shame because otherwise it’s not a bad looking walkway.

If you’re looking for help planning your landscape project and you want to be sure that the crews know what needs done, contact us for a consultation. We’d love to help your front walk look gorgeous – and not like a zipper.


When landscape architecture serves the client perfectly

Sometimes you work with a landscape design client and an idea pops into your head. You think “wow, this is great! I just cleverly summed up the client in a bold visual statement and they’ll love it!” When this happens at 2 am you often look at it the next day after a few hours of sleep and decide it wasn’t as brilliant an idea as you had hoped. In this case, though… ok, here’s the finished photo, a plaza outside the science building at UC Irvine:

plaza landscape design

Can you guess what the patterning and layout represents?


Cellular mitosis! How brilliant is that? To whichever landscape architecture or design firm came up with this one, I am impressed.

Are you looking for a landscape design that captures your unique spirit and sensibilities? Contact us and let’s see what we can do for you!

When Should I Have My Irrigation Installed – Before or After Planting?

This is a question I get quite a lot. In an ideal world, this is the order of operations:

  1. All planting areas are prepped
  2. Trees and shrubs are planted
  3. Irrigation system is installed
  4. Perennials and mulch are installed

There are several good reasons for this. First, the guys planting the trees and shrubs can swing wildly with picks and shovels without fear of hitting a buried irrigation line. Second, the irrigation guys know exactly where the trees and shrubs are, so they can position the heads and adjust the spray so they’re not hitting shrubs. If it’s an extensive planting job and the irrigators get there first, there will be lines run right where trees and shrubs need to go. Mr. Murphy and his law will see to that.

If your irrigation company and your landscape company won’t coordinate with one another, well… that’s the level of service I provide. I’d love to talk to you about your project.

How Much Does a Retaining Wall Cost in Northern Virginia?

I recently spoke with someone who was looking for a retaining wall, four feet tall and ninety feet long. Before moving forward with a consultation he wanted a sense of what such a wall would cost.

He was surprised, to say the least.

There are a lot of design consideration for retaining walls in northern Virginia, and every site is different. Slope, soils, access, permits, and existing conditions impact the costs, so it’s not generally practical to create a proposal for a retaining wall based solely on square foot pricing. The best contractors examine the site, create a landscape plan (or have a landscape designer create a plan), work out all the materials needed down to the number of tubes of adhesive, and base the price on the labor and materials required to build that individual wall.

That said, I will use square foot numbers to at least start the conversation so I can help the client decide if they’re ready to move forward with the design. When we multiply the length of the wall by the height we get the total square feet of face, or SFF. Here’s how different materials can break down by SFF. Keep in mind that these are not absolutes, just starting points. Your site conditions may result in higher or lower costs.

Pressure-treated 6×6 retaining wall: Generally, a wall of this type will start at $35-45/ SFF. So in the example conversation with the homeowner who had a 90’x4′ wall (360 SFF), he’s looking at approximately $12-16K.

Segmental retaining wall: these are your interlocking concrete wall systems, EP Henry, Techo-Bloc, or similar. Depending on a lot of variables, walls average from $50/SFF to $75/SFF. For our homeowner with 360 SFF of wall, we’re looking at approximately $18-27K.

Concrete retaining wall with stone veneer and cap: This is the most attractive type of wall, and one I’m a huge fan of. Costs vary by site conditions, stone used, etc., but I generally ballpark $75-105/SFF when discussing budgets. My sample homeowner with 360 SFF would be looking at a range of $27-38K.

There are other types of walls (boulder, dry-stacked fieldstone, poured and stamped concrete, etc) but the above are far and away the most commonly requested and built in the DC Metro area. As you can see, retaining walls have the potential to use a good portion of the budget for a landscape project. This is why good design is key. Not only can a good landscape master plan ensure that the walls are where they need to be and and properly designed, it can potentially reveal options for using fewer or smaller walls – freeing up funds for the more exciting parts of the project.


Checking In: Retail Garden Center Design

Several years ago, one of the landscape contractors I’ve worked with in New England contacted me. He had purchased an old transmission shop and was interested in turning it into a retail garden center and operations base for his landscape company, and needed a design. It was certainly a challenging piece of property:

Nice for a transmission shop, I guess, but not for a nursery.

We talked about space planning and flow and I worked closely with the engineer who did the site plan, as she had some very stringent requirements for sight lines and parking that she had to adhere to.

Since we had to convince the Town Selectmen and the Department of Transportation that our ideas were awesome, I also created some 3D renderings:


The plan sailed through approvals, and several years later I was finally able to swing by and take a look at the finished product. Changes were made to the plan to reflect budget and how they came to use the space, but I like how it turned out!




Principles of Design: Rhythm in the Landscape

You’ve heard designers talk about “moving the eye through the space.” That’s what rhythm does. Human beings, by our very nature, look for patterns. Rhythm sets up those patterns, leading the eye to the next point, and the next, and the next. There are five flavors of rhythm:

  1. Repetition and alternation
  2. Progression or gradation
  3. Transition
  4. Opposition or contrast
  5. Radiation


Repetition is a common means of creating rhythm and moving the eye through a space. Look at the columns supporting the aqueduct, below. Your eye immediately scans down to the arch at the very end.

See? You can’t even fight it. Colonnades, fenceposts, even an allĂ©e of trees coming down the driveway, all employ rhythm to move the eye along.

Alternation is a repeating sequence of two or more things, from which the eye will discern a pattern and follow along. This is another technique that has been used for centuries, as you can see in this reproduction of an egg-and-dart moulding.

Progression or Gradation

The most common use of progression is in the use of shapes progressing from smallest to largest, or vice versa. A really simple example of this is “wedding cake” or “hatbox” steps:

credit: everything about concrete

Please note that this is not an endorsement of wedding cake steps – see how easy it would be to miss the first step coming down and break a leg? – but you can see how it does lead your eye to the door. Again, it’s setting something up in such a way that your eye wants to follow it.

You can also achieve this effect with color, progressing from light to dark or dark to light, although you’re more likely to see this type of color progression used in interior design.


Transition leads the eye from point A to point B with no interruption. Look at the top photo of the aqueduct. The trough atop the columns helps lead the eye in this way, as would a beam on a trellis as shown below.

You don’t necessarily need structure to pull this off, however. The purple grasses in the planter below act as a backdrop to the golden perennials, but they also serve to draw the eye across the planting bed.

Opposition or Contrast

Opposition uses abrupt changes to create rhythm and interest. A common example of this is repetitive 90 degree angles, like in grids or rectilinear designs. I know, you’ve seen this patio in my portfolio, but I like it and it illustrates the concept beautifully.

Opposition is also found in patterns where stark opposites are next to one another – light and dark, or angular and soft, for example. I haven’t done it, but I think a really cool application of this would be clipped boxwood alternating with angular hunks of polished granite. How cool would that be on a big estate property?


Radiation + spiders will give angsty young men the ability to crawl up walls. Radiation in design creates a lot of visual movement through the use of concentric circles or spokelike forms. Radiation is really cool when used in a single plane, like the flooring in a lobby or even the entrance of a Target store. When taken into all three dimensions and terra-formed, it’s exceptional. Amphitheaters are pretty neat; this is flat out wild:

credit: Dave Lindoo in Peru

So there you have it: five ways that rhythm can be used in landscape design to move the eye through the space. Up next: emphasis!

Landscape Design for Commercial Properties

Just as in residential landscape design, the first impression is key with commercial landscape design. In fact, it’s even more important. After all, you’ll still sit down and visit with Aunt Edna even if her front yard sports petunias in a white-painted tractor tire, but a bed and breakfast doesn’t have sweet Aunt Edna. Good landscape design is about more than just stopping cars, however. It’s important that customers can safely walk around the grounds of your property, and you don’t want to spend an arm and a leg maintaining it all. I’ve found that there are some common mistakes commercial property owners make when it comes to their landscaping.

Wrong plant, wrong place – This is basic to all landscape design, but it’s especially problematic in a commercial setting. If a plant gets too large for the space, it’s a maintenance nightmare and can be a hazard to customers. If it’s too small for the scale of the building, it makes the landscaping (and the business) look cheap. Finally, most businesses have a lot of pavement relative to plant beds, which is hard on plants that aren’t heat and drought tolerant.

This is a shot of a building down the street from my office that does a great job of illustrating wrong plant, wrong place.

Bad bed design – If the bed is too big, there are huge expanses of mulch that either have to be hand weeded or chemically controlled. If the bed is too small, the plants can get damaged by cars, mowers, or pedestrians. Bed shape can make a big difference in terms of maintenance costs as well. Big, smooth curves that don’t require a lot of backing up or trimming save time, which in turn saves money. Commercial landscape maintenance is a game of margins, so you know your mowing company has figured out their man hours to the minute.

Poor layout – How many places have you been to where the grass (or plant beds) have been trampled by people making a beeline for the door? If you plan your paths appropriately, people will stay on them. The first commercial design client I ever had was a property manager for a small apartment complex. He was tired of tenants cutting across the grass to get to their cars, so he wanted the meanest, nastiest hedge I could come up with. Wouldn’t it have just been easier to lay out better paths?

Here’s a picture of what it can look like when paths aren’t planned out well.

credit: Phil Gyford (click to visit his flickr page)

In my time as a designer I’ve worked with wineries, garden centers, home builders with model homes, and even the owners of a large shopping center. I get it – the goal is to get the maximum impact for the least cost. I encourage business owners everywhere to think about how their landscaping can impact the top line (sales) and the bottom line (operations). A professional landscape consultation can result in huge savings for years to come.

What To Plant Under Power Lines

Photo credit: The Garden Professors Blog (click for link)

I don’t have to tell you this is bad, right? Wrong plant, wrong place and all that? Obviously you’ve seen examples of corrective pruning to deal with improperly located trees, but it’s better for everyone – homeowner, arborist, and tree – if we select a tree that will give us the look we want without growing into and around the wires.

If you live in Virginia, it got even easier to select a tree for under power lines. Did you know that Virginia Tech has a Utility Line Arboretum on campus, where you can view locally appropriate trees that will play well with power lines? How cool is that? The folks at Tech selected many of the trees from this list of Utilitrees, an excellent resource for designers, homeowners, and landscape contractors.

Some of my favorites to use under or near power lines include Serviceberry (Amelanchier), Crabapple (Malus), Golden Rain Tree (Koelreuteria – featured here), and tree lilac (Syringa reticulata). Take a look at the list; I’ll bet you can find something you’ll love that will work well for years to come.

6 Screening Plants That Aren’t Leyland Cypress

UPDATE! There’s a new post up on planting for privacy – be sure you check it out!

My name is Dave Marciniak and I hate Leyland Cypress. It’s unattractive before it fills out, it’s no prize once it does fill out, it gets way too big (30′ wide and 50-60’+ tall) for the suburban lots on which they’re planted, and bagworms consider them a tasty snack.

I’ll admit that Leylands are, in part, an easy target for my ire because they’re often used in a really boring manner. I get that you have an unattractive view you’re trying to screen, but lining up as many of a single plant as you can plop in the ground is just boring. Emerald Green Arborvitae is another plant used this way.

See? One more reason not to browse the web on your phone while driving – you might have just fallen asleep and wrecked your car, thanks to this photo.

It’s the same problem at any scale. Our friends over at a local winery wanted to put up an evergreen screen along an edge of their property that they may end up sharing with some new neighbors. Can’t say that I blame them. Who would want to give up a view like this?

Anyhow, a local nursery recommended throwing a row of White Pines across the property line. Yawn. You’re a nursery, do better! So I developed this plan for them:

Let’s look at each plant I used here:

1- Cryptomeria japonica ‘Yoshino’: I’ve talked about this one before, as it’s a favorite. With an eventual height of 30-40 feet and a spread of 12-20 feet, it’s a well-behaved tree that will hide a multitude of sins in the neighbor’s yard. It’s a quick grower, too.

Photo credit: Middlesex Conservation District

2- Black Pine: A tougher pine than the common builder’s favorite, white pine, the black pine will easily grow to 20-30 feet or more, with a similar spread.

Photo credit: gardensandplants.com

3- Deodar Cedar: Bluish-green foliage and a height of around 50 feet make this tree an interesting specimen to mix into an evergreen screen.

Photo credit: Morton Arboretum

4- American Arborvitae: this is a great choice for narrow locations too. Overall height ends up around 25-40 feet, with a spread of 10-15 feet.

5- Kwanzan Cherry: Now wait, you say, this isn’t an evergreen! And that’s true. Part of eliminating a problem view is blocking it; but another component is misdirection. When these trees get covered in their gorgeous pink blooms in springtime, no one’s going to be looking at what’s beyond.

Photo credit: Bemis Farms Nursery

6- Maple: We actually used a Commemoration Sugar Maple, which gets a great blaze orange color in the fall. At 50 feet tall and 40 feet wide, this will be another great foreground tree throughout most of the year. These and the cherries allowed us to create a layered planting, which makes it look more like a farm windbreak and less like a suburban “hide the neighbors” screen.

The bottom line is that just because you have something you want to hide from view doesn’t mean that the best way to do it is with a single, straight soldier row of the same boring plant. Play with texture, play with color, and use some tricks that not only block the view but give the eye a reason to look somewhere else.

Unsure of where to start? Give me a call or email to set up a consultation, and I’ll help you get started.

Green Giant Arborvitae are another great alternative to Leyland trash trees!

Plant Profile: Golden Rain Tree

These beauties have mostly stopped blooming at this point (although I’ve seen an oddball bloomer here and there), and now the big, dangly seed pods are doing their thing. Koelreuteria is a good choice for spaces where you want a reasonably moderately-sized tree with a later bloom time than some other trees. A lot of designers are using them as street trees. This photo was taken along Vandor Lane in Manassas, Virginia; another great spot to see some Koelreuteria is along the alley and parking area behind Davis Street in Culpeper, Virginia.