Larry Miller Subaru Turf to Xeriscape Conversion

The folks over at the Boise Larry Miller Subaru had a problem: the two south facing areas of turf in front of their showroom looked nice enough, but demanded an obscene amount of water. Worse, over-spray from the broadcast irrigation was staining their shiny new Subarus.

As a sponsor/supporter of the Idaho Botanical Garden, naturally Larry Miller Subaru turned to IBG for turf alternative ideas. IBG horticulture director Toby Mancini, sketched up a plan that included creating berms in the two areas out of a specific soil "recipe" (25% organic compost, 25% fractured 1/4" gravel and 50% screened topsoil), especially formulated for xeric, zonally adapted plants. The plants he specified read like a list of the "who's who" list of dependable, drought tolerant and readily available specimens, perfect for the dry intermountain west. They included:

Philadelphus lewisii 'Blizzard'

Fallugia paradoxa

Agastache rupestris

Panicum virgatum "Heavy Metal'

              Nepeta racemosa 'walker's low'

Oennothera macrocarpa subsp. incan 'Silver Blade'®

Echinacea x 'Cheyenne Spirit'

Thymus pseudolanuginosus 

We jumped at the opportunity when Toby asked us if we be interested in the installation and were able to complete the project in a single day (including the conversion of the broadcast sprinkler system over to single source drip system for each plant*).

Clean up after a long day.

Fresh installation = lots of negative space. By mid-summer next year, the plants will really start filling in.

*I generally prefer broadcast irrigation because I believe it promotes good lateral root development as well as a vibrant soil ecology. This is a great example, however, where drip was the right way to go to eliminate wasteful over-spray as well as runoff from the berm. Our preferred approach is to loop a 1/4" line with 6" emitter intervals all around each plant, making sure that each 1/4" line is directly connected to a 1/2" feed line for even water volume throughout the bed and even distribution of water around each plant.

Industrial Park

While Corten is often associated with modern gardens abiding by rules of strict linearity and an emphasis on negative space, I was delighted to find panels of oxidized steel sprinkled throughout a woodland garden during a design consultation earlier this summer. The warm, earthen tones of the rusting panels leapt out of the shadows and contributed to a visceral feeling of movement throughout the garden. I took this as the starting point for the design of an  outdoor room in a woodland garden.

A concave 8' x 9' oxidized steel panel acts as the back wall and abstract focal point "painting" for the room. An arcing, andesite stone wall, green roof arbor and steel edging all add to the feeling of an open, yet delineated space within the garden.

A Yankee doodles.

In the process of developing the design, I experimented with using concentric circles as a way to bridge from the right angles of the home/patio to the fluid, curvilinear lines throughout the garden.











The vertical expression of these concentric circles (the panel, the arbor and sloping andesite wall) are all critical in defining the space.

A completed concept. No, wait- the rocks are too much.

The home is in a neighborhood nestled against the Boise river that provides a micro-climate achingly close to zone 7, with trace amounts of honest-to-gosh humidity and an actual water table; perfect for the dry, woodland, under-story plants we installed.

                                   

Just another Mendelssohn/Front 242 mashup.

The process...

Before the intervention.

Construction of the andesite wall and steel panel base.

Kevin Knickrehm attaching the green
roof arbor to its i-beam armature.

I almost like it as well unplanted. Almost.

                                       
                                                       

                                                 

As I was flying by.

          

   

So We Left the Tree Zoo for a Night…

I’ll let you in on a secret: I've been complicit in my own kidnapping every father’s day for the last seven years. Regardless of how busy the landscaping season is, we ditch the City of Trees (AKA the tree zoo) and head to the mountains to see the real thing- the “real thing’ in this instance being an actual forest that doesn’t require my help to sustain it.*   

I ran feral in an eastern hardwood forest as a young child, so I’m always a little surprised to find myself surprised to see a self-sustaining forest.  Boise is a great place to live, but by the middle of June the foothills have already lost their brief, verdant veil and begin to don an increasingly washed out, brown aspect.

What a difference 60 miles and several thousand feet of elevation can make.

The old Forest Service guard house we lovingly refer to as our “time share”,  sits next to Beaver Creek about 30 miles north of Idaho City. Hiking east along Beaver Creek will connect you to the Crooked River trail system and more wild trees than you can shake a stick at. And not just trees but shrubs, grasses and forbes with nary a drip emitter to be seen!

The very underutilized Buckwheat (Eriogonum).

Perennial geranium

Wild heuchera happily anchored in a granite outcrop.

Color. Texture. Form.

When I combined sedum & heuchera in this project, a friend remarked how odd they thought this combination was.  Ha!

First time I've seen this wild clematis. I definitely need to find out more about this plant!

Yep, that's a landscaper's hand.

Back to Boise.

*   Full disclosure/laborious backstory: When I was MUCH younger, I rappelled out of helicopters to suppress fires in an effort to “sustain” the forest. This wasn’t too long after Yellowstone had erupted into an enormous bonfire. Debate still rages on in regards to proper “forest management”, but for the sake of the story can we just forget about life in the so called Anthropocene? Please?

The Vertivore's Edible Green Wall

If I was to draw a Venn diagram showing the overlap of my gardening and landscape interests, you'd probably find edible green walls smack in the center, next to medieval Japanese stonework and my fig tree.

Oh look, I did.

Up to this point I've mostly written about green walls as an ornamental element, but vertical space is also a terrific place to grow an edible garden. My long term goal for our own property is to place an edible component within three or four steps anywhere on our acre. We're lucky to have so much room, but with the continuing trend of urbanization and smaller lots, many people don't have the room to grow greens and veggies conventionally. But if you've got a wall, there's a way.

Skyfarm: Gordan Graff

Optimistic futurists love to present us with images of a biophilic, urban paradise not too far away.  Heavy on stunning visuals and light on actual details, this hazy vision usually includes rendered images of urban agriculture on the walls and rooftops of the city skyline.

Part of a larger concept called Agriculture 2.0, this discussion of urban of food production rarely takes into consideration some of the problems that need to be solved to make this vision real.

Soil based green wall systems, for example, are very heavy, requiring serious engineering for the support armature.  GLTi's 2,380 square-foot living wall in Pittsburg has an estimated weight of 24 tons when fully saturated. Some have even described this kind of urban farming as financially nonsensical.*

Personally, I think it makes a lot of sense, if the design challenges can be addressed. To that end I started experimenting a few years back (successfully, I might add) with a lightweight mineral wool system.

So far, we've grown nasturtiums, chard, tomatoes and dozens of varieties of herbs including rosemary, thyme, sage, mint, basil and oregano.

This year I plan to try out collard greens, rainbow chard, spinach, rapini and cabbage.

Rest assured I'll be sharing pictures of our edible green wall through the season.


*But the author seems to have some internal conflict on the matter as demonstrated by this article.

How To Prevent Your Tree From Falling Over

Far too many Boise trees blow over during relatively light wind storms. It's in the tree's best interest not to perform a faceplant, so why does it happen so often?

Based on years of post mortem evaluation, Jason shares tips on how to prevent your tree from falling over. Head on over to the D&B Supply blog for more.

~Stacy

Dem Bones ... The Importance of Scale and Style in Hardscape Construction

I've yet to be involved in a project where the home and the landscape are designed at the same time (does that even happen anymore?). Generally, I'm given a completed plan view of a house perched on abstract topography. This is my opportunity to get the bones of the landscape right the first time around.

What do I mean by that? Most of our installation projects consist of improving existing landscapes. Often this involves adjusting the scale and style of the hardscape components of the landscape (things like patios and walkways), to compliment the scale and style of the home; details that should have been considered the first time around.

I'm astonished at the amount of effort and creativity in home design that promptly stops at the outside edge of the home, but you certainly won't find me complaining. Every undersized 4' x 8' patio paired with a 4000 sq. foot house is just another project in waiting.

Here's the plan I originally received for a job we're currently working on.

Deliciously blank.

Later the architect gave me an updated plan showing the driveway sweep and proposed entrance walkway (floating rectangles that somehow resolve the 5 foot elevation difference between the driveway and the front door).

This thumbnail sketch of my counter proposal for the entrance walkway reveals a less direct route to the front door. This is where I am trying to set the cadence and tone for the entire landscape, taking cues from the architecture and style of the home. (Read: creating the illusion that the home and landscape were actually designed in thoughtful tandem.)







Home construction delays put this project so far out that I'd nearly forgotten about it, but following a break in the cold weather, the entrance walkway was finally installed last month.

There's quite a bit of work yet to do (for example, covenant restrictions require all vertical surfaces to be natural stone, cultured stone or stucco), but it's gratifying to see a harmonious setting for this magnificent home finally begin to materialize.

Updates to follow (more hardscape and then here come the plants!) ...

10 Mile Interchange Hellstrip

Fitter, happier

Am I the only one who finds this repeating motif on the new(ish) Ten Mile Interchange just a bit creepy?

Aside from the undertones of Orwellian Maoist thought control, The Ten Mile Road Interchange in Meridian, Idaho represents a subtle change in public works projects around Ada County. Gone are the days of shoulder to shoulder asphalt and concrete. Honest to goodness, live plant material and permeable surfaces are beginning to be incorporated into new design.

But, as I was often reminded as a child, they don't give you a medal for good intentions, so let's perform some taxpayer deconstruction of the project.

PLANTS

Behold, an Idaho winter: a washed out/monochromatic sky meets a washed out/monochromatic planting bed.

What? I'm not being fair because it's February? While it is true that last summer there was a lovely succession of color here, compliments of Echinacea purpurea, Coreopsis verticillata, Perovskia atriplicifolia, Gaillardia, and Leucanthemum x superbum, they are all now distant herbaceous memories from a half forgotten warm season.





Winter "structure" is mostly provided now by the skeletons of miniature Berberis, the carcasses of winter kill Lavendula, prematurely trimmed ornamental grasses, and the much maligned Yucca filamentosa.

(Incidentally, I swear I will punch the next person who tells me that "there's a reason they call them YUCKas". I mean, cut them a little slack, they are the only plants in this bed providing any real color for five months of the year!)

I think lavender is great and I probably overuse it in my designs, but what is there not to like? It's mildly drought tolerant, the bees love it, it smells terrific and it blooms for months.

There are plenty of varieties of  lavender that are dependably hardy in our area, but I'll be surprised if even half the lavender in these beds wake up in the spring. They really don't catch a break between the basalt "mulch" heat sink in the summer and snow plows and drunk drivers in the winter.

Which leads us to...


MULCH/HARDSCAPE

Un-shaded asphalt surfaces can reach temperatures as high as 160 degrees. A planting bed surrounded on all sides by asphalt and concrete receives a tremendous amount of this as reflective heat. What is the logic of using dark, basalt mulch in the beds to further heat up the poor plants?

Crushed basalt is also a nightmare to maintain.




Another observation: the median beds are elevated, surrounded by slope faced curbs. Perhaps a better approach would have been to match the planting grade with that of the road and install curb cuts for passive rain harvesting?

IRRIGATION

The purple cap on the popup gives us the heads up that non-potable water is being used. In many areas of the country that means reclaimed, grey water with potential problems associated with salt build up. Not here. Snow melt is what built Boise and our urban forest and I'm so pleased to see it being used in place of domestic water.

As a card carrying member of the "green industry" I'm expected to hate broadcast sprayers and embrace drip lines and micro-irrigation, but too often micro-irrigation = dead plants. This is partially due to incorrect installation (single emitters rather than grid installation), but also because our soil has lousy capillary action resulting in uneven distribution of water and poor root development.


CONCLUSION

There's a lot to like about this project- for about 8 months of the year anyway. Swapping out even half of the standard army-green Yucca filamentosa with a variegated form (Yucca filamentosa 'Bright Edge' or 'Color Guard'), or the bluish Yucca rostrata would give this planting a lot more punch during our indeterminable "gray season".

The damaged lavender along the edges of the median strip should probably be replaced with a tougher, semi-evergreen perennial that can take the heat and drive-over damage; maybe Penstemon pinifolius or Arenaria 'Wallowa Mountains'?

Since I'm feeling generous, I'll say that the crushed basalt "mulch" is slightly better than paving over a garden bed.  I'd really like to see an organic mulch installed (or at least light colored, porous sandstone if you must have rock). I'm sure the crushed basalt was installed out of an assumption that an organic mulch would blow out onto the street and the rock would stay put. You can see how well that's working.