By Deborah Horn
Conifers once ruled the
world. Long before the first magnolia opened a shy bud to a passing pollinator,
conifers covered much of the globe. They still rule in the Northwest, where our
cloudy winters favor the low-wattage, year-round photosynthesizing style of our
As slow-growing versions of
the mighty conifers we see all around us, dwarf cultivars can create a
distinctive Northwest feeling within the confines of a small garden or even a
balcony container. These small trees bestow big benefits, as they are
long-lived, low-maintenance and can provide food and shelter for wildlife.
There is some flexibility
in the usage of the term “dwarf.” The designation generally applies to a
conifer that grows two to ten inches a year. Yet dwarf conifers can range in
size from tight sea urchin-like buns that only grow an inch or two a year to a
scaled-down version of the coast redwood, which—while reaching only 20 feet
rather than 320 feet—is not what most people think of as a dwarf.
Some of you may have
experienced the “dwarf” that (ever so slowly) outgrew your original plans for a
space. This is because the term dwarf often applies to a tree’s rate of growth,
not its eventual size. For this reason, it is important to consider what the
eventual size might be. If the smallest of the small is just right for you,
look for dwarfs categorized as “miniature,” which means they only grow one to
two inches a year.
Many of our classic dwarf
and miniature conifers come from “witches brooms.” Witches brooms are clusters
of abnormal foliage that are found on the branch of a normal tree. These
growths are caused by genetic mutation, and may be propagated to retain
miniature (or other) features. Other times, dwarfs are simply individuals which
are genetic variants of normal species.
Designing with Dwarf
There are at least three
Northwest garden styles where dwarf conifers can play a key role: Asian,
alpine, and Northwest native.
Japanese and Chinese
gardens have showcased dwarf conifers for centuries. If the twisted, wind-swept
look of a pine is what makes the garden feel Asian to you, then a variety of
the Japanese white pine (Pinus parviflora)
may be the best choice. ‘Glauca Nana’ grows six to ten inches/year and will
reach five to eight feet in ten years. Rod Parke, who tends a dwarf conifer
garden in north Seattle, has a variety called ‘Koru’ which he says grows “very,
very slowly.” One often used for bonsai because it has wonderful, corky bark
and a dense blue pyramid shape is P. Parviflora
The dwarf forms of the
Japanese Black Pine (Pinus
thunbergii) have a fuller, compact
look when compared to the Japanese white pine, and certain cultivars, such as Pinus
thunbergii ‘Thundercloud’ have stunning white candles (new
growth). ‘Koto buki’ is a smaller version of this much-admired dwarf. It has an
upright shape, deep green (shorter) needles, and fat white candles—all in a
package that grows six inches or less a year.
The Hinoki cypress, Chamaecyparis
obtusa, with its deep green, scalloped fans, has dozens of
diminutive cultivars from which to choose. The dwarf variety ‘Verdoni’ sports
bronze/white/yellow highlights on a loose, open cone shape to six feet in ten
years. A stunning group of them grows at South Seattle Community College’s
Coenosium Rock Garden. The cultivar ‘Mariesii’ is similar, but grows to only
half that size.
Naturally, dwarf conifers
(specifically, the miniatures) are right at home in the alpine garden. Here we have
gardens that aim to capture the spirit of those high, rocky places. Trees in
the shape of cushions, buns and globes charm us the way only miniatures do—we
can’t believe a tree can be so tiny!
for stone troughs and small rock gardens, Chamaecyparis obtusa
‘Golden Sprite’ grows only one-half inch per year. Pinus
leucodermis ‘Smidt’ has densely packed pine foliage and grows to
only two feet tall in 20 years. Rod recommends the miniature Mugo Pine
‘Jacobsen’ which in his garden has grown only a couple of inches in a decade.
Perhaps a few of us (including myself) have mistakenly planted the straight
species, thinking it was a dwarf. Big mistake.
cushion plants dwell among the gravel or scree, vertical conifers can provide
structural contrast with columns of bright green (Chamaecyparis
lawsoniana ‘Ellwood’s Gold Pillar’), sage green (Cupressus sempervirens ‘Totem’),
or gold (Juniperus communis ‘Gold Cone’).
A favorite of Rod’s is the lacy, dark green, spiraling form of Thuja
occidentalis ‘Degroot’s Spire’. This narrow column can reach ten
Alpine gardens can also be
Northwest native gardens, and there are a few excellent dwarfs that come from
native stock. The Kruckeberg
Botanic Garden is home to a 40-year-old miniature tree that is just two feet
lasiocarpa ‘Du Flon.’ This variety
was found by friends of
the Kruckebergs, Bita and Alton DuFlon, as a seedling subalpine fir on the
those of us who want to create native gardens in a limited space, even the
shore pine, Pinus
contorta var contorta, which eventually reaches 20 to 30 feet, might be too
tall. Luckily for pine lovers (which include chickadees and finches) there are
some truly amazing dwarf forms of our natives. Pinus
contorta ‘Spaans Dwarf’ grow three
feet tall by four feet wide in ten years, with short, dense needles on a
windswept branching pattern. If it is gold that you seek, look no further than Pinus
contorta var latifolia ‘Chief
Joseph’. It is a medium green in summer, but in winter—just when we need it the
most—this one turns a brilliant gold that reminds me of the elusive gold of our
alpine larch (Larix
layallii), which, unfortunately,
won’t grow in captivity.
Caring for Dwarf Conifers
It is important to provide
dwarf conifers with proper conditions. Good drainage is usually required,
especially for members of the chamaecyparis (false cypress) clan such as C.
lawsoniana. Never place a soaker hose directly above the root
ball of a chamaecyparis—you’d just be asking for trouble. Few dwarf conifers
are actually drought tolerant, though most like sun. For a low-water-use area
Rod suggests Pines and, “any tree with glaucous foliage, because the blue color
is actually a waxy coating that prevents moisture loss.” He suggests yews, hemlocks
and cryptomerias for part shade, but would never consign any conifer to total
shade, not even the hemlocks.
doing a little research beforehand, and selecting the best cultivar for your
garden situation, you will find how much a little tree can contribute to the
If you’d like to adopt one
of these enchanting trees, you can “shop” for just the right dwarf by visiting
gardens that feature them before you actually buy. There are a number of places to
view dwarf conifers.
Community College Arboretum/Coenosium Rock Garden, Seattle, Washington. The
garden, on the SSCC campus, is open to the public. Its purpose is to “showcase
many of the better dwarf conifers that are available from specialty nurseries
and are little known to the public.” SSCC is located at 6000 16th Ave. SW,
Seattle, WA 98106, phone 206-764-5300. The SSCC arboretum web site is:
Conifer Display Garden
at The Oregon Garden. This destination garden’s conifer display possesses one
of the largest collections of dwarf and miniature conifers in the country. It
was developed in partnership with the American Conifer Society, Western
Chapter. The Oregon Garden is at 879 W. Main St., Silverton, OR 97381, phone
Garden – Shoreline, Washington. Beneath a mature overstory of conifers, island
beds containing dwarf conifers and native plants are interspersed over four
acres. MsK Rare Plant Nursery is also located on the property. Free self-guided
tours during open hours; guided tours are available. KBG is at 20312 15th Ave.
NW, Seattle, WA 98160, phone: 206-542-4777.
Garden. The Bellevue Botanical Garden in Bellevue, Washington has an alpine
rock garden that features diminutive evergreens and allies. It is located at
12001 Main St., Bellevue, WA 98005, phone: 425-452-2750.
If you have a favorite
dwarf conifer resource, e-mail us at email@example.com and we’ll share
it with readers on our web site. NWGN