Friday, September 24, 2010

Hebe in the Cascadia Garden

Hebe recurva & Daboecia cantabrica 'Rainbow' July 2010
 
Hebe anomala September 2010

Hebe cupressoides September 2010 

 
Hebe glaucophylla September 2010 

Hebe ochracea September 2010 

Hebe x pimeleoides 'Quicksilver' & Calluna vulgaris 'Wickwar Flame' September 2010 

Hebe salicifolia September 2010

Hebe is 1 of my favorite genera, an extremely useful group of shrubs for gardens in Seattle, the coastal Pacific Northwest & northern California.  There are 90 to 100 species of Hebe, all but 1 native to New Zealand.  There are numerous hybrids & cultivars.  Hebe are mostly small shrubs, some low & sprawling.  Some have very lovely flowers, but foliage is the main attraction for most Hebe.  Foliage comes in a range of green & gray, with some red & purple.  Hebe grow quickly, which make them very useful for filling open spaces.  Many Hebe become leggy, which some people find unattractive.  I find this trait an opportunity to weave Hebe together with other open, low-growing shrubs such as Calluna, Cassinia, Daboecia & Olearia.  In my garden I combine Hebe x pimeleoides 'Quicksilver' with Calluna vulgaris 'Wickwar Flame'.  This makes a very eye-catching display of gray & yellow foliage.  It never fails to impress garden visitors.  I appropriated the idea from a garden I once visited & have spread it on to others.  I combine Hebe recurva with Daboecia cantabrica 'Rainbow' & Hebe anomala with Cassinia leptophyllaHebe was the ancient Greek goddess of youth.  Homer referred to her as, 'Hebe of the slender ankles.'  These slender ankles (Hebe seldom grow a stout trunk) allow other plants to rub against them like a swarm of friendly cats.  Hebe buxifolia & Hebe topiaria have dense branching patterns that make them useful replacements for Buxus sempervirens & Ilex crenataHebe cupressoides  & Hebe ochracea are known as whipcord Hebe.  They grow in alpine regions of New Zealand.  Many of the other Hebe used in Seattle are sub-alpine in nature.

List of Hebe in the Cascadia Garden
Hebe anomala (removed due to extensive damage 2010)
Hebe ochracea
Hebe x pimeleoides
Hebe x pimeleoides ‘Quicksilver’
Hebe pinguifolia ‘Pagei’
Hebe recurva  (some damage 2010)
Hebe ‘Red Edge’
Hebe salicifolia  (badly damaged 2010)

Update: In November 2010 there was a hard frost.  Temperatures had been unusually warm, with a high of 56F/13.3C on 11/16, until they dropped to 31F/-0.5C on 11/21, 22F/-5.5C on 11/22, 16F/-8.8C on 11/23, 14F/-10C on 11/24, 28F/-2.2C on 11/25.  Then temperatures were above freezing.  This damaged or killed many plants.  Hebe anomala & Cassinia leptophylla were so badly damaged that I removed them.  Hebe salicifolia was also badly damaged.  Much of the damage didn't show until later in the year, as many branches continued to die.  Hebe recurva had some damage, but recovered well that year.  The rest had no damage at all.  I saw some damage to Hebe topiaria in other gardens.

Friday, September 17, 2010

The Brian O Mulligan Sorbus Collection

Sorbus anglica September 2010
 
Sorbus aria 'Salicifolia' September 2010

Sorbus bristoliensis May 2010

Sorbus cashmiriana May 2010

Sorbus forrestii September 2010

Sorbus forrestii May 2010

Sorbus gonggashanica September 2010

The Brian O Mulligan Sorbus Collection can be found at the Washington Park Arboretum in Seattle.  This collection is the most complete in North America, containing 77 different taxa (species, forms, hybrids & cultivars) divided into sections for simple-leaved & compound-leaved forms.  The collection was named in honor of Brian O Mulligan, Director of the Washington Park Arboretum from 1947 to 1972.  His interest in Sorbus guided the renovation & redesign of the collection.  According to Mulligan, writing for the Spring 1990 edition of the Washington Park Arboretum Bulletin, the 1st plantings of Sorbus were made in 1949 & 1950.  As of 1990, when the collection was renovated, there were 50 taxa.  Most of those were raised from seeds received from many arboreta & botanical gardens, mainly in Europe.  27 new taxa have been added since 1990, including several important Chinese species. 

Sorbus is a genus of 100 to 200 species of trees & shrubs in the family RosaceaeSorbus species are commonly known as whitebeam (simple-leaved forms) & mountain ash (compound-leaved forms).  Sorbus aucuparia (rowan) is the most common species of mountain ash found in the Seattle area.  Unfortunately, it has become a weed that has given the genus a bad reputation.  Among the 100+ species are many that make excellent garden trees.  The City of Seattle approves Sorbus aucuparia 'Michred' & Sorbus x hybrida as street trees.  The Sunset Western Garden Book calls Sorbus, 'good small garden trees.'  The Hillier Gardener's Guide to Trees & Shrubs says, 'Sorbus is one genus that provides ornamental features throughout the year & does so without needing much care.'

Among the most beautiful & often-used species are Sorbus aria, Sorbus cashmiriana, Sorbus commixta & Sorbus hupehensis.  I believe Sorbus scalaris has the most beautiful flowers.  In my own garden are Sorbus 'Birgitta', Sorbus forrestii & Sorbus gonggashanica.  I have raised seedlings taken from Sorbus hupehensis & Sorbus rehderiana in the Brian O Mulligan Sorbus Collection.  But of course, with so many other species nearby, those are likely to be hybrids.  A blog devoted solely to Sorbus is Rowans, Whitebeams and Service Trees written by Dr Patrick Roper.

List of plants & their number in the Brian O Mulligan Sorbus Collection
Sorbus alnifolia  2
Sorbus anglica  2
Sorbus americana  2
Sorbus amurensis  1
Sorbus aria  2
Sorbus aria f. longifolia  2
Sorbus aria 'Lutescens' 1
Sorbus aria 'Salicifolia' 1
Sorbus aucuparia 1
Sorbus aucuparia 'Cardinal Royal'  1
Sorbus austriaca  2
Sorbus 'Birgitta'  2
Sorbus bristoliensis  1
Sorbus caloneura  2
Sorbus cashmiriana  3
Sorbus commixta  12
Sorbus commixta 'Embley'  1
Sorbus dacica  3
Sorbus decora  1
Sorbus devoniensis  3
Sorbus discolor 'Apricot Queen'  1
Sorbus domestica  3
Sorbus esserteauiana  1
Sorbus filipes  5
Sorbus folgneri x Sorbus alnifolia  1
Sorbus forrestii  3
Sorbus gracilis  1
Sorbus gonggashanica  1
Sorbus helenae 1
Sorbus himalaica  1
Sorbus x hostii  2
Sorbus hupehensis  2
Sorbus x hybrida  2
Sorbus x intermedia  1
Sorbus japonica  1
Sorbus javorkae  1
Sorbus koehneana  3
Sorbus kusnetzovii  1
Sorbus lanata  2
Sorbus latifolia  2
Sorbus megalocarpa  1
Sorbus x meinichii  1
Sorbus meliosmifolia  1
Sorbus microphylla  3
Sorbus minima  2
Sorbus mougeotii  1
Sorbus pallescens  3
Sorbus prattii  1
Sorbus pogonopetala  1
Sorbus porrigentiformis  1
Sorbus poteriifolia  1
Sorbus pygmaea  1
Sorbus randaiensis  1
Sorbus redliana  1
Sorbus reducta  1
Sorbus rehderiana     1
Sorbus rehderiana form     1
Sorbus rehderiana 'Joseph Rock'  1
Sorbus aff. rehderiana  3
Sorbus sargentiana  4
Sorbus scalaris  3
Sorbus scalaris hybrid  1
Sorbus scopulina var. cascadensis  5
Sorbus x splendida  1
Sorbus subcuneata  1
Sorbus subsimilis  1
Sorbus tamamschjanae  1
Sorbus thibetica  1
Sorbus x thuringiaca 'Fastigiata'  1
Sorbus torminalis  1
Sorbus turkestanica  1
Sorbus umbellata  1
Sorbus umbellata var. cretica  3
Sorbus ursina  2
Sorbus vestita  1
Sorbus 'Wilfrid Fox'  3
Sorbus zahlbruckneri

Friday, September 10, 2010

Cougar Mountain: Overgrowth & Understory

Cougar Mountain Regional Wildland Park covers 3,100 acres between between 1,000 and 1,595 feet above sea level near Issaquah.  It is the largest of the King County Parks, 6 times the size of Discovery Park, the largest park in the City of Seattle.  Cougar Mountain Regional Wildland Park is connected to Squak Mountain State Park by the Cougar-Squak Corridor.  Together they cover an area of 5,000 acres.  The park is mostly forested, but also contains significant wetlands.  Overgrowth & Understory is a temporary outdoor sculpture exhibition at Cougar Mountain Regional Wildland Park, which runs from July 10th through October 2nd, 2010.  16 artworks near the Sky Country and Anti-Aircraft Peak trailheads explore themes of art, nature, and land use.  This is collaboration between King County Parks and the Center on Contemporary Art.

Cougar Mountain Regional Wildland Park August 2010.  Burnt Offering by Debra Harvey.  ‘Burnt Offering begins with the charred stump of a once large sheltering tree. Forged copper, rusty metal, rebar, semi-precious stones & glass mosaic combine to become part of the rebirth...the creation of the understory.’  Overgrowth & Understory

Cougar Mountain Regional Wildland Park August 2010.  Retablo by Aaron Haba.  ‘Retablo is a response to the abandoned infrastructure on Anti-Aircraft Peak.  Drawing from the history of the site's use to deploy Nike missiles, I chose to work with simple geometric shapes.  These refer to boundaries, both physical & spiritual, & how over time these boundaries change, or in the case of the site become obsolete.  Through the use of ashes, flowers & chalk I hope to explore the need for boundariess & how we can dismantle those that keep us from seeing the world as a whole.’   Overgrowth & Understory

Cougar Mountain Regional Wildland Park August 2010.  Mushroom growing along Anti-Aircraft Ridge Trail.

Cougar Mountain Regional Wildland Park August 2010.  Alder (Alnus rubra) forest on Anti-Aircraft Ridge.

Cougar Mountain Regional Wildland Park August 2010.  Que Viva El Sol / La Vida Del Sol by Miguel Edwards.  ‘The sun is massive...but also gaseous.  With this piece, I hoped to capture the essence of the duality with bold structure & geometry, as well as gesture & negative space.’  Overgrowth & Understory