Salem Hardy Plant Society, PO Box 2027, Salem OR 97308-2027
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Pruning Clematis by Linda Beutler, Curator, FRCC

Simple Truths:

Clematis are not low-maintenance plants. Clematis cannot read or count. They do not know in which pruning group they are. You cannot kill a clematis by pruning it. For every rule about clematis, there is at least one exception, usually more.

Many more clematis rebloom than you realize. RHS research has discovered that 8 of 10 cases of "clematis wilt" are actually stem breakage, fertilier overdose, improper watering, or pest damage, not Phytoma clematidina.

Revised (Realistic) Pruning Simple Truths:

There is no such thing as a clematis that requires little or no pruning. Clematis that flower early are best pruned immediately after flowering. They may be pruned back to whatever degree you deem necesary. This can be done every year. or not.

Late-flowering LFHs, and Clematis viticella crosses with C. florida (obvious by their dark stamens), will flower on old wood if not hard-pruned in winter("Venosa Violacea', 'Minuet', etc.)

The Texensis Group are herbaceous perennial vines, and with the exception of 'Sir Trevor Lawrence', their old wood will not rejuvenate.

Early-flowering LFHs will rebloom well if hard-pruned immediately after their first flowering in May / early June.

Most of the Atragenes Group cultivars will rebloom more than once if dead-headed immediately after each flush of bloom.

Any clematis can have its vines rejuvinated by being pruned to whatever degree you deem necessary, immediately after flowering. In the case of late-flowering species, hard-pruning in autumn (after flowering) produces ample rejuvination the following spring.

A Visit to Elk Rock Garden at Bishop's Close

Spring is a good time to visit one of Oregon’s most unique landmarks: Elk Rock Garden. The six-acre garden is unique in that it occupies a sloping hillside below Portland’s Macadam Blvd. and the Willamette River. Peter Kerr, a Scottish immigrant and successful businessman, started the garden in 1912 on what is essentially a basalt shelf several hundred feet above the river. Now owned by the Episcopal Diocese of Oregon, Elk Rock Garden is open daily from 8 a.m. to 5 p.m. and is free.

We began our visit by taking the upper path directly south of the parking lot, following it all the way to the southern most point of the garden. Along the way we passed through banks of epimedium, daphne, moss-covered rock, boxwood hedges, a variety of conifers, and two enormous gold-blossom berberis. The north end of this path overlooks the parking lot and, in May, one of the most spectacular displays of purple wisteria in Oregon. As you proceed be sure to take in the spectacular magnolia blooming in the lower (main) garden below as well as trillium on your right. You’ll walk through tree-sized rhodies on your way to the southern viewpoint, where a bench awaits at the base of a sprawling madrona, with an expansive southern view of the Willamette. Continuing east and north back into the main garden and lawn you’ll see banks of hellebore and acers. Arriving at a small footbridge you’re treated to a series of small ponds below. Beds of pink and white anemone and twiggy fothergilla will greet you as you pass through more rhodies, tree camellias, enkianthus, a stand of stately oaks, beds of bluebells, false solomon seal and Brunnera ‘Langtrees’. On the way you’ll pass a glorious loropetalum, ‘Pipa’s Red’, a 9' by 9' beauty. As you continue toward the garden’s north end you’ll pass a line of corylopsis as well as one of the tallest Spanish firs you’re likely to see in Oregon. Finally, you’ll arrive at the base of two mammoth sequoias, planted, we suspect, when the garden was started a century ago.

Elk Rock Garden is located halfway between the Sellwood Bridge and Lake Oswego at 11800 S.W. Military Lane. Note: there is no restroom and food/picnicking are not allowed. ~ Newsletter article by Tom Marsh

Vine Maple:America's Answer to Japanese Maples

Our Northwest native vine maple, Acer circinatum, may be the most widely planted Northwest native in western Oregon. It’s a dependable single or multi-stemmed little tree with much to offer. It gives color at nearly all times of the year. More specifically, it gives us red through twelve months of the year.

Beginning with spring, its flowers sport red and white. After flowers come the green leaves. And, soon after flowering starts the samaras, or seeds, begin growing. As they mature the samaras become reddish. Samaras from the earlier flowers are almost mature when the tree finally ends flowering.

Come fall and with maturing samaras, the leaves take on various hues of red and yellow. If conditions are right, the leaves can become a brilliant red. “Right” is not too much shade nor too much soil moisture.

Upon leaf fall, twigs have the opportunity to show their reddish color, earlier hidden by the leaves. Reddish twig color continues through winter until flowering begins in spring, and beyond.

The green leaves, spring-fresh, are like circles with big teeth, called lobes. Most leaves will have seven lobes, but some may show an additional lobe or two. Occasionally some have fewer than seven lobes.

As with many plants, vine maples are not averse to sporting forms that differ from the majority. This has enabled the introduction of a number of cultivars –plants selected and/or propagated by humans – into the trade through recent years.

Perhaps the earliest cultivar to be introduced was ‘Elegant’, selected by Hubert Rhodes in the Skagit Valley in 1954. Its seven-lobed leaves are a little smaller and slightly more incised than usually found. Overall it’s a small and seedy plant.

One of the earlier discoveries was the “cut leaf” form named ‘Warner Monroe’ or simply ‘Monroe’ for the late Dr. Warner Monroe, an avid hiker and philosophyprofessor at Warner Pacific College in Portland. Dr. Monroe took a few cuttings and submitted them to the late well known maple authority, J. D. Vertrees of Roseburg, Oregon for propagation. Vertrees named the plant for Dr. Monroe, and introduced it into the trade.

As an aside, I hiked with Dr. Monroe a couple times, a real challenge. The diminutive 5-feet-6-inch wiry Monroe could out-hike most. On one of the hikes he shared where he found the vine maple named for him, in the McKenzie River watershed. A few years ago I saw it now growing as undergrowth beneath other shrubs. A specimen of ‘Warner Monroe’ vine maple can be seen in Bush Pasture Park with other Oregon native trees and shrubs, just east of the main parking lot near the Bush house and barn.

Not long after Monroe’s discovery, Del Loucks of Del’s Lane County Nursery of Eugene introduced a lacy, deeply cut, five-lobed leaf vine maple called ‘Glen-Del’. It was named for Loucks and the well known nurseryman Glen Handy from east of Portland. ‘Glen- Del’ has a narrow upright growth habit.

Other cultivars of vine maple have continued to be introduced. ‘Mono’ and ‘Fascination’ have leaves similar to ‘Monroe’. ‘Pacific Sprite’ has leaves with fewer than the usual seven lobes. Leaves of Pacific Purple®, also known as ‘JFS-Purple’, emerge bronze, deepen through summer, and hold color into fall. The seven-lobed leaves of ‘Sun Glow’, aka ‘Sunglow’, change from peach to light orange in spring, to medium green in summer, then to red and purple in fall. ‘Sun Glow’ only grows to about 3 feet tall and wide. ‘Pacific Fire’ has brilliant orange-red to red twigs. ‘Little Gem’ and ‘Little Joe’ are smaller in stature. ‘Little Gem’ is densely twiggy. I saw it at the home of Noble and Willetta Bashor east of Salem, only about 2 feet tall. ‘Allyn Cook’, aka ‘Alleyne Cook’, is a dwarf upright form. Other introductions include ‘B&SWJ 9565’, ‘Burgundy Jewel’, ‘Sunny Sister’, and ‘Whitney Broom’.

– Wilbur Bluhm