Tuesday, September 18, 2012

Fantastic Native Cultivar: Amsonia 'Blue Ice'

Amsonia 'Blue Ice' in my garden late April next to Nepeta 'Walker's Low' & Phlomis

Who needs a compact, attractive, tough-as-nails perennial that--by the way--is gorgeous in two seasons?  Yes, everyone.  Then let me enthusiastically endorse Amsonia tabernaemontana 'Blue Ice.'

The horticultural world is still rightfully swooning over its feathery cousin, Arkansas Amsonia (Amsonia hubrichtii), recent winner of the Perennial Plant of the Year.   I will make the claim, however, that Amsonia 'Blue Ice' may be the more versatile and durable plant.

Amsonia 'Blue Ice' was discovered in a seedling block of Amsonia tabernaemontana at White Flower Farm in Connecticut.  It sports the same broad leaves of the species, giving it a handsome texture to contrast with finer-foliaged plants.  But it seems to be more compact (12-15 inches in height), longer blooming (three weeks + in my garden), and has this incredibly dark blue color of the bud of the flower.  Dark blue is incredibly rare in perennials.  The dark blue buds have this incredible shadowing effect underneath the lighter blue periwinkle-like flowers.  In the mid-Atlantic, it bloomed late April through early May.

Dark blue buds shadow the lighter blue open flowers of Amsonia 'Blue Ice'

Amsonia tabernaemontana is a member of the dogbane family (Apocynaceae).  Like other members of the dogbane family, it has a white, milky sap that is toxic to mammaliam herbivores--perhaps making this a deer-resistant plant?  (Have others of you grown this plant in deer country?  I'd be curious to know how it fares.) It grows natively in rich open woods, rocky woodlands, limestone glades, and moist sandy meadows.

'Blue Ice' is a hybrid, but the exact parentage of this cultivar is still unknown.  Tony Advent of Plant Delights Nursery guesses it is a cross with the taxonomically-debated dwarf Amsonia montana (which most nurseries seem to categorize as Amsonia tabernaemontana 'Montanta').  Others have wondered whether it is a cross with the Asian Rhaza orientale, which after looking at images of Rhaza, seems highly plausible.  Whoever the papa is, Amsonia 'Blue Ice' has proven to be incredibly tough.  I planted it where it spills over a public sidewalk.  The heat off this sidewalk regularly tops 95 degrees for weeks in the summer.  And yet the foliage remains steadfast and handsome.    Based on my two year trial, I'd recommend it as a replacement for groundcovers. 


The foliage of Amsonia 'Blue Ice' in the midsummer heat near the U.S. Senate office
In the fall, this Bluestar turns a golden yellow, though  not quite as brilliant as its Threadleaf-cousin (A. hubrichtii).  Fall color was ok the first year, and much better the second year.  The warm yellow autumnal foliage is nice in combination with low grasses and native deciduous shrubs.


The fall foliage of Amsonia 'Blue Ice' is good, though not as strong as A. hubrichtii

The success of two U.S. native Amsonias (A. tabernaemontana and A. hubrichtii) should convince plant breeders to explore more of this wonderful genus.  Piet Oudolf has used Amsonia tabernaemontana var. salicifolia to great effect on projects such as The Highline and the Lurie Garden.  This variety differs from the species in that is has narrower more lanceolate leaves that makes it more willowy in texture.  There are at least 22 known species of Amsonias--most native to North America--and many of them have horticultural potential.  Southeastern natives Amsonia illustris and Amsonia ludoviciana are two others worth noting.  I'm particulalry interested in the Louisiana native A. ludoviciana for its compact habit, heat tolerance, and whitish, whooly undersides.  Could be a great native groundcover that might have some deer tolerance.  Plant hunters and breeders, get to it!

Amsonia hubrichtii in fall is incredibly dramatic

Tuesday, September 11, 2012

Landscape Architecture's Finest Moment?

Is the profession of landscape architecture entering into a new golden age? If the 2012 ASLA awards are any indication, the answer may be yes.


Award of Excellence: “A Green Sponge for a Water Resilient City: Qunli Stormwater Park,” Haerbin City, China. Design by Turrenscape and Peking University, Beijing. Photos by Kogjian Yu.

Landscape architects have long lived with a dualistic view of the profession. Inside the profession, LA’s see themselves as heirs to Frederick Law Olmsted’s heroic and sweeping ambitions. Landscape architects shape cities, create National Parks, protect the environment, and even stimulate social reform. But this rather ambitious internal view of the profession is undercut by landscape architecture’s relative obscurity in the public eye. Introduce yourself as a landscape architect at a cocktail party and questions about lawn mowers, flowers, or plant diseases immediately follow. Since Olmsted, the chasm between what landscape architects think they do and what the majority of them actually do has been very deep. Until now.

Landscape architects may indeed be gaining influence. “Landscape urbanism,” the theory that landscape—rather than architecture—is more capable of organizing and enhancing cities has moved from obscure theory to the dominant pedagogy in design-related higher education. Large scale urban projects all over the world are being lead by elite landscape architecture firms rather than by architects. Landscape architecture is moving away from merely ornamenting buildings and instead shaping the very infrastructure of cities.

The 2012 ASLA Awards are another indication of landscape architecture’s emboldened scope. The awards feature a stunning array of projects, including a seven thousand acre stormwater park; a park highlighting urban agriculture; a former quarry turned garden; the defining memorial for 9/11; and two new botantical gardens that feature not just plants as horticultural objects, but the ecological relationship between them.

Honor Award: “Quarry Garden in Shanghai Botanical Garden,” Shanghai China. THUPDI & Tsinghua University.

What is remarkable about this year’s ASLA Awards is not just the variety of projects, but the ambition of each of them. The Qunli Stormwater Park in China shows that a gorgeously designed recreational park can also be a green sponge for the entire city. Lafayette Greens in Detroit shows how an engaging public space can also be a productive vegetable garden. The Arizona State University Polytechnic Campus shows how the ecological fabric of the Sonoran desert can be a setting for a campus. Canada’s Sugar Beach shows that playfulness and whimsicality can contribute to the beauty of an urban waterfront.

What’s different about these projects is not just their scope, but their voice. The names of the projects by themselves—“Quarry Garden,” “Green Sponge for a City,” “Sugar Beach,”—suggest the extraordinary dramatic authority that is at the heart of all these projects. These projects are not about making spaces that slip quietly into their context; they are instead a declaration of war. Their anthem is a simple: landscape matters.  Lanscape architects are no longer decorators of architecture; they are green knights who march foward with with the conviction that any outdoor space--from quarries to waterfronts, from gardens to cities--can be conquered with design.

Honor Award: “Canada’s Sugar Beach,” Toronto Waterfront. Claude Cormier Associes Inc. Images by Claude Cormier Associates and Nicola Betts.


Honor Award: “Lafayette Greens: Urban Agriculture, Urban Fabric, Urban Sustainability,” Detroit, Michigan. Kenneth Weikal Landscape Architecture.  Images by Beth Hagenbuch.


Honor Award: “Sunnylands Center and Gardens.” Rancho Mirage, California. The Office of James Burnett. Images by Mark Davidson and Dillon Diers.

For the full list of the 2012 ASLA Awards, including more images and fuller project descriptions, click here.

Tuesday, September 4, 2012

Thirty Seconds Until You are Totally Inspired

Several weeks ago, I wrote a post comparing texture in music to planting design.  The other day, I read this quote by one of my favorite landscape architects in the world, London-based Tom Stuart-Smith, which also compares music to the garden.  Like everything he does, the quote is simple, yet briming in shimmering detail.  Enjoy!

"I rarely listen to music while I’m working since I cannot concentrate.  But instead, some musical phrase takes up permanent residence in a chamber of my ind and accompanies me through the day.  In one very facile respect music is like a garden, with its contrast between form and content.  The formal structure of music is often quite rigid, as with sonota form, which is then contrasted with the embellishment of detail. 

"With Beethoven’s late quartets and piano sonatas, contrast is taken to an extreme: an almost savage starkness and sparse construction is set against passages of eloquent lyricism or gaping silences.  If this music depicts anything, it is a succession of emotional experiences.  Perhaps this is like a garden, with its crescendos and diminuendos, its sudden bursts of energy and silences—all set within an overriding architecture.  Doesn’t the garden at its best become an abstract expression of man’s connection to the world beyond himself?  Like music . . . but just a little less turbulent than Beethoven.” 

Landscape architect Tom Stuart-Smith.  Quote originally appeared in Garden Design Journal, September 2004

Monday, September 3, 2012

Garden for a Modern Pavilion


I was pleased to see a garden I had recently worked on featured in the fall issue of Home and Design Magazine. My involvement in the garden began when director Elliot Rhodeside of my firm, Rhodeside & Harwell, introduced me to a long-time friend and client of his. The client had hired local architect Robert Gurney to design a modern pool house for his Bethesda home. Elliot had designed several phases of the garden several years before and oversaw all aspects of this garden design.

Robert Gurney is a celebrated modernist architect. For this project, he created a jeweled glass and stone pavilion to sit atop a new swimming pool. The old pool was ripped out and a new pool was created to connect the house and pavilion. Gurney sensitively sited the pavilion as far back against the existing woods as possible to ground the structure in vegetation.


The existing planting beds did not relate at all to the new structure, so our challenge was to blend the pavilion into the landscape and the woodland behind it. To that end, Elliot and I enlarged the planting bed and focused on a palette of perennials and grasses to create a foreground for the pavilion. The planting also had to blend the orthogonal geometry of the pool and pavilion with the more curvilinear geometry of the existing lawn. To add structure to the garden, clusters of boxwoods were added at key corners. These clusters will eventually grow together and be clipped into gumdrop shapes. Behind the pavilion, we planted a grove of Stewartias with Palm Sedge grass (Carex muskingumensis ‘Oehme’). We wanted to intensify the feeling of woods immediately behind the pavilion.  Elliot suggested the row of columnar Magnolia 'Alta' that flanks the fenceline along the pool.  These stately trees draw screen the neighboring property and draw the eye toward the pavilion.