Soft yellow flowers of Corylopsis pauciflora . ( Photo courtesy Richie Steffen / Great Plant Picks )
CASCADIA Berberis nervosa , Cascade mahonia , is a lovely native groundcover , especially for a shady or semi-shady location . It is particularly striking when massed beneath trees and shrubs . Growing up to two feet wide and four feet high , it produces long , wonderfully architectural evergreen leaves , each consisting of 9 to 19 glossy , bristle-toothed leaflets . Small , bright-yellow flowers are held in erect clusters above the foliage in April / May . By late summer , these develop into handsome , waxy blue berries . Cascade mahonia does best in moist , well-drained soil . It can handle full sun , where the foliage turns a plum color , but I prefer the rich-green foliage color of the shade-grown plant . Formerly known as Mahonia nervosa , it colonizes slowly via underground runners .
A stately , deciduous tree with deep-darkgreen foliage and gray , fissured bark , Quercus garryana ( Garry oak ) should be grown in every garden that has the space to showcase it . In cultivation , trees can reach up to 75 feet high and wide ! The maritime habitat of this native tree has been drastically reduced since 1839 , the year botanist David Douglas named it ( in honor of Nicholas Garry , an officer of the Hudson ’ s Bay Company ). A great shade tree , Garry oak should be sited in a sunny location . Don ’ t have room for a large tree ? The specimens of Garry oak in the Cascadia Forest at Pacific Connections are actually a shrubby variety native to the Siskiyous named Quercus garryanna var . breweri . Commonly called Brewer ’ s oak , it reaches up to 15 feet high with a spreading habit .
Among the most graceful of small trees , Tsuga mertensiana ( mountain hemlock ) is a knockout in any landscape . With fine-textured foliage and nicely layered branching , the
The foliage and developing fruits of Berberis nervosa . ( Photo by Niall Dunne )
Foliage and flowers of Garry oak , Quercus garryana . ( Photo by Joy Spurr )
s l e n d e r c o n i f e r grows slowly to 35 feet tall in cultivation . ( In the wild , it can reach up to 200 feet .) Plant it in lean , well-drained soil in full sun to light shade .
NEW ZEALAND Most of the Southern Hemisphere ’ s 90 or so species of hebe ( now all lumped into the genus Veronica ) are from New Zealand , and many varieties are available in area nurseries . Among the most attractive and reliable of these is the subshrub Veronica topiaria . With its dense , rounded form and attractive glaucous foliage , it combines perfectly with other plants , providing contrast in scale , form , color and texture . After
14 v Washington Park Arboretum Bulletin