landscape design – The Garden Professors™

When worlds collide

This past week I was in Alnarp, Sweden to present at the International Urban Tree Diversity Conference. Lots of interesting talks, posters and field tours. Much more to discuss than I can fit into a blog post, but if you’re interested you can read the presentation abstracts.

One of the best features of the conference is that the presenters and participants included not only arborists and urban forester but also landscape architects and urban planners. This might not sound too remarkable but these groups are not always on the same page. While urban foresters are on board with the need to diversify urban and community forests; species diversity can be at odds with uniformity, which is a key element in landscape design. For example, a common application of uniformity in design is the installation of alle’s – long, uniform monoculture plantings along a street or path.

Fredicksberg alle in Copenhagen - street view — Fredicksberg alle in Copenhagen – street view

Fredicksberg alle in Copenhagen - pedestrian view — Fredicksberg alle in Copenhagen – pedestrian view

The aesthetic appeal of an alle’ is undeniable and seemingly universal. We saw many examples in our tours in Malmo and Copenhagen, but alle’s can found almost anywhere mankind has planted trees.

The dilemma, of course, is that any monoculture planting runs the risk of catastrophic failure, especially in an era of increased global trade and potential introduction of destructive exotic pests.

Simply planting a random mix of species leads to a menagerie effect – one of these, one of those – that most eyes find unsatisfactory.

A random mix of species increases diversity though not necessarily aesthetic appeal

One of the challenges addressed at the conference is how to meet the design and aesthetic objectives of uniformity while still achieving diverse landscape. There are no simple solutions and like most compromises, not everyone will be completely satisfied. But at least we are getting to the point where all sides of the discussion are being heard and creative minds are melding the science and the art that will produce the desired aesthetic and diversity.

What to do when it’s still raining?

It’s almost May…and it’s still raining. Even for our normally wet spring climate, this has been an unusually soggy year. I’m also blaming the weather on my 3rd or 4th cold so far this year, which has knocked me flat for the last 6 days (which was why I had no Friday puzzle posted). So in between blowing my nose, hacking my lungs out, and generally feeling sorry for myself, I started looking over 10 years’ worth of photos of our home landscape.

You’ve seen bits and pieces of this before in some of my postings. But one of the spots I’m most proud of is the tiny east-facing side yard that originally contained lawn, a lilac, and a border of arborvitae. Within the first few years the lawn came out and plants started going in. In 2004 I’d installed some small rhododendron, a redbud (left foreground), and a whole lot of woodchips:

Since then we removed the lilac (it had been planted too close to the garage and was a powdery mildew magnet), put in an arbor and wisteria (on the right), and added a few more plants (ferns, bleeding hearts, various bulbs and tubers, etc.). Here it is two (2006) and five (2009) years later:

This year we’ll finish off the area with some flagstone pavers.

One of the main reasons I’m so pleased with this area is that it was inexpensive to redo and it established quickly. We bought the redbud, the wisteria, and the bulbs, but the rest were donations from friends’ gardens, or volunteers that popped up elsewhere in the yard, or plants that someone else wanted removed (like the larger rhody in the far left corner and the dogwood in the right foreground, 2006 photo). The chips were free; the flagstones were a major score from craigslist (free to whomever would pry them up and lug them out). All the purchased trees and shrubs were barerooted; and root-pruned if needed before planting. Upkeep is minimal except for a bit of pruning and spot watering during the hottest summer months; we’ve lost no plants other than the occasional bulb poaching by squirrels.

It’s just a little bitty sideyard…but I enjoy walking through it every time I’m outside, even in the rain.

Landscape design – fatal flaw

So many great answers…so many problems with this landscape! Everyone who made a comment was spot on in their reasoning. And each of these flaws was completely preventable with good design. But I’m not sure I would have been able to predict the problem that I now see every week at this location:

his area is the only access point for service vehicles of any persuasion. And sometimes they DO park on top of the planting strip. Fred’s designation of these ground covers as “Stompus flatii” was perfect!

Lesson to be learned: sometimes it’s best NOT to have planting strips if they clash with the realities of site use.

Friday quiz – landscape design

Down the street a ways from where we live is a relatively new condo complex wedged between a hill and the street. A narrow planting strip separates the sidewalk from the street, as shown below:

The driveway at the top of the photo bisects the planting strip and dead ends in the parking area for the condos. I have photoshopped this a bit, for reasons you’ll see on Monday. But this is a true representation of the landscape.

I’d originally taken photos of this area for my ongoing “why trees die” collection (since all but one died within 2 years), but there’s something else wrong in this landscape related specifically to the design. Can you figure out what it is?

Answers and more photos Monday!

Why won’t landscapers use mulch?

A few weeks ago I was in Olympia (it misses you Bert!) reviewing grant applications. As I tend to do whenever I have time and my camera, I set out in search of gardening goofs that evening. Here’s the edge of a relatively new commercial site I discovered:

OK, not too bad so far. We’ve got a nice stone mulch next to the curb, then a lovely groundcover, in flower, that also functions as a living mulch. But what’s that we see in the upper half of the photo?

Yes, it’s Canada thistle (Cirsium arvense), an aggressive perennial weed that spreads by stolons and can make dense monocultures of prickly nastiness. In fact, the front is already advancing on our little groundcover:

Had the landscapers continued with mulching the soil rather than leaving it bare, these thistle seeds might not have germinated. But for whatever reason, the bulk of the landscape was left bare:

I’m sorry, but this just looks ridiculous. There was some obvious care in laying the stone mulch and groundcover, but then the landscaper seems to have run out of time and/or money and just plopped in some bulbs and corms. It reminds me of a birthday cake.

I don’t understand the rationale behind this. Was this a real design? Did the client run out of money? Or (as the more cynical side of me wonders) was this done deliberately to create a high maintenance landscape requiring lots of weeding in the future?

Thoughts?

Shear lunacy

I subscribe to Digger magazine, the industry publication from Oregon Association of Nurserymen. I am always curious about trends in the nursery industry and this magazine is a good way to find out what home gardeners are buying.

The cover feature of the May 2010 issue is on topiary. While I can appreciate topiaries in formal gardens – with dozens of gardeners to keep them shaped up – I think they are poor choices for most home landscapes. Shearing plants to maintain a particular size or shape is a never-ending activity that most homeowners will tire of quickly. Nevertheless, the magazine reports that topiaries are becoming more popular for home landscapes, especially along the East Coast. The article showcases the newer topiary shapes – stars, crosses, angels, even cacti – in addition to the traditional spirals and poms.

The article warns growers that skilled employees are needed to prune topiaries properly, and that the time commitment to create and maintain topiaries is significant. One grower states “it’ll take a fair amount of time to shape it, and then you’ll be trimming it lightly a couple of times a year until you sell it.”

Curiously, the article says nothing about either the time commitment or pruning skills needed for homeowners who purchase topiaries.

Even more curious…the subsequent issue of Digger is devoted to sustainability. Seems a bit of a disconnect there.