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DETAILS
It was an overcast day in June and I was on my way to the Gifford Pinchot National Forest. As I left, the clouds hung low, hiding the hills to the northeast that were my destination. I trustingly took to heart the weather forecast of ‘clearing by noon’. Barely an hour later I was traveling at about 2500’ and climbing, in and out of clouds which were never as thick as they seemed from below, but certainly not about to clear.
1995 was the year of the Bear Grass (Xerophyllum tenax). Some combination of environmental and internal mechanisms had set them to blooming with wild abandon. Almost every clump of silvery foliage sported masses of 3’ stems of creamy white flower heads. It was an amazing sight. The clouds never did dissipate, but the scene coming and going in the shifting mist was beautiful. It was actually a welcome foil against the intrusive blocks of clearcuts that are too abundant in this area. Even though I had traveled this road many times before, each turn revealed a new and unfamiliar vista. The open hills were covered as far as my limited vision would allow with bear grass flowers that at times seemed to float above the misty, moist ground. It had a very unreal, diffuse quality about it. It was all I could do not to drive my Trooper off the side of the road. The air was cool and moist and felt good on my skin. (A ghost of a cloud sits on the road before me. Confidently I plunge ahead. It touches my cheek with a cool caress as I enter, and lets me pass.) Patches of ragged clouds were coming and going, along with great banks of almost imperceptibly moving mist. I would look away for a minute and the scene would change, mysteriously. It was a sight and a feeling that will stay with me for a long time. It is the reason that I have never, for an instant, been sorry to have made the move to the Pacific NW from my native Chicago 16 years ago, and will never take for granted the gift of living here.
The point of this article, sentimental digressions aside, is the amazing amount of plant variation around us. I spent a good deal of time looking at the details of Bear Grass on my foray that misty day. Just as no two humans are alike, so it is with plants. (with exceptions, horticulturally speaking - perhaps the subject of a different article.) But the nature and purpose of wild seedling grown plants is genetic diversity, and this is what makes up most of the natural world around us.
There was Bear Grass with stems of green, of light brown, of deep reddish brown, to almost black. The shape of the flower head varied considerably, some narrow and upright, some wide and opulent. The head of Bear Grass is made up of hundred of individual flowers, and on most of them, the pedicels (stems of the individual flowers) were short and upright, giving the entire inflorescence a club-like effect. However, on some, the pedicels were much longer, giving the flower head a very lax appearance, like a pendulous starburst. Once I became aware of this quality, I saw quite a bit of it throughout the day. Most of the plants had creamy white ovaries, matching the color of the petals, but occasionally there were plants with lavender colored ovaries, a small but attractive detail. At the base of each individual flower is a small narrow bract. Creamy green was the norm, but occasionally, these bracts were almost black. This was a lovely effect, especially in the still budded portion of the flowers, with these bracts interspersed among the tight white buds.
There is variation to be observed everywhere, and at every season. Close inspection of Iris tenax, for example, reveals a large array of shapes, sizes, intensity of color, and spotting of the individual petals. Both Disporum smithii and D. hookeri var. oregana can be quite diverse. I have observed them with dark brown stems, with wavy leaves, with extra wide leaves, and very narrow leaves, and even found a variegated form with a clean white edge. Leaf shape can vary considerably in Vine Maples, as does the fall color, from yellow, to orange, to bright red. The ubiquitous Douglas Fir varies in growth habit. The branches may be upright, laying out flat, or somewhat pendulous. The form of the tree may be sparse and narrow, or quite wide and full. The density and color of the needles can differ from tree to tree, giving an overall effect of deep rich green, dull green, or occasionally a glaucous tone.
Plants develop a particular form or flower as an adaptation to the environment, to attract a pollinator, or to survive the elements. One very basic law of nature is that the strong survive. It is those with a genetic structure that allows them to adapt to a changing environment that will live on during times of stress or change. Much of this adaptation has to do with things we don’t see, such as hardiness or disease resisance, and that quality may make the difference between survival or death of a species. As a nurseryperson, I tend to look at plants with an eye for their ornamental qualities. Many of the plant varieties that we grow in our gardens are the result of wild selected forms with some perceived superior quality of flower, form, hardiness or disease resistance. However, in my other guise of amateur botanist, I am fascinated by the logic and the intricacies of the plant world.
Both environment and genetics contribute to plant form, as they do to human development. A few years ago, in the Siskiyou Mountains, we were looking for unusual forms of Asarum hartwegii. This beautiful species of Wild Ginger normally has various silver markings on the leaves, usually along the veins. Most populations we find are in shady areas along spring flowing creeks which dry by summer. Occasionally we come across an exceptionally marked form. This day, growing in full sun directly in the loose rock on the side of the road, we found a patch with pure silver leaves. Heavy silvering of leaves is often an adaptation to living in sunlight. Perhaps this one with a tendency to having silver leaves was better able to survive in this sunny situation, where its seedling siblings were not able get a roothold - environment and genetics at play. (I did manage to bring a small piece of this home and it has remained silver in it’s new environmant, with just a small bit of green in the center of the leaf. Seedlings from this plant are also mostly silver, showing that this is a genetic trait being passed on.)
Much of what may seem like genetic variation is actually an adaptation to the particular environment. An example of this are the many dwarf and prostrate trees and shrubs at high altitudes that are merely physical responses to the harsh winds or snow pack. When planted at our elevations they quickly revert to the normal form. But there are so many examples of true genetic variation - Eriophyllum lanatum (Oregon Sunshine) shows much deviation in dissections of the leaves and compactness of plant. Penstemon cardwelli varies in density of foliage and abundance of flower. We once came across a Western Hemlock (Tsuga heterophylla) with totally pendulous branches, lying flat against the trunk. The tree was about 30’ tall, and about 3’ across. (This is a very desirable form from a nurseryman’s viewpoint.) Albino flowers and variegated leaf forms of plants are also occasionally found, and always a treat to come across. On casual hikes this summer I have seen white flowered Sidalcea oregana, white Polemonium pulcherrimum, a gold striped Veratrum viride, a gold leaf form of ‘Sitka Alder’ and an Oregon Boxwood (Pachystima myrsinites) with gold and green variegated leaves.
Variation is everywhere. Observation of these small differences is a fascinating study, and can add another dimension to a walk in the woods or on a mountain trail, or even an afternoon drive.
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GROUNDCOVERS FOR SHADY AREAS
English Ivy - it can sometimes be a blessing, with shiny, evergeen leaves, fast growth, and an ability to seemingly grow anywhere (and then some), but too frequently it’s a curse - and most of the cursing seems to come from those who have lived with it a little too long. If “Ivy, ivy everywhere” is your lament, take heart dear gardeners, there are other choices. For those of us who seem to have to cover up any bare piece of ground in our custody, I‘d like to suggest a few alternatives that may take the edge off the ivy boom.
One of the best, in my opinion, are any of the epimediums. There are many species and forms of this extremely adaptable plant to choose from, ranging from 10” to over 2’ tall. The somewhat leathery leaves are divided into 3 to 9 crisp, heart-shaped leaflets on thin wiry stems. Panicles of small delicate flowers with elongated spurs dangle like little columbines above the emerging foliage in spring. The flowers can be yellow, white, pinkish-lavender, orange, or red/white, often with contrasting colors of petals and sepals. There are spreading forms with evergreen leaves that turn bronzy or reddish in winter, and deciduous, clumping forms with a pleasing apricot-yellow fall color. Hardy and long lived (there are some 50 year old clumps in a New York garden), they have the distinct advantage of being able to compete with roots of nearby trees and shrubs. Epimediums will grow in considerable shade but tolerate sun with sufficient spring watering. Following are some of the more readily available varieties: bright yellow E. pinnata ssp. colchicumand soft yellow E. versicolor ‘Sulphureum’ are evergreen spreading forms; E. x ‘Rubrum’ is a semi-evergreen clumper with red/ white color and reddish fall/ winter foliage; E. grandiflorum has the largest flowers of the group, about 1” across with long graceful spurs, usually white, deciduous and clumping; E. x youngianum ‘Roseum’ (pink) or‘Niveum’ (white) have a more delicate wildflower charm. Any of the clumping forms can be planted ‘en masse’ to eventually fill in the allotted space. Our native Vancouveria hexandra (Inside-Out Flower) is very closely related to Epimedium, but has more delicate leaflets and sprays of small white flowers to 12”. It fills the same niche under similar conditions. It will also tolerate root competition and forms a weed smothering mat with time. Although deciduous, it is an excellent and attractive choice. Epimediums are members of the Berberidaceae Family along with such shrubby genera as Mahonia and Berberis, and the herbaceous genera Achlys (Vanilla Leaf) and the east coast Jeffersonia. To see exceptional stands of epimediums as groundcovers, be sure to visit ‘Bishops Close’ in the spring.
NW native Oxalis oregana can be invasive, but is a good choice in the right situation. Growing to about 6” high, the large clover-like leaves are almost translucent when unfolding in early spring, especially pretty in the dappled sunlight beneath deciduous trees. The flowers are pinkish white, but a fine form with extra large deep pink flowers is available. An area under trees that is well drained and stays fairly moist is a good spot to try a combination planting of Oxalis underplanted with deep rooted tuberous plants such as Trillium and Erythronium. Try planting Oak Fern (Gymocarpium dryopteris) Vanilla Leaf (Achlys triphylla) and Vancouveria hexandanearby and each will find it’s own niche as they intertwine to form a cool tapestry of textures and shades of green all summer long, following a quiet symphony of ephemeral spring bloom. Oxalis ‘Wintergreen’ is new on the market, denser growing and deeper green, each leaf ornamented with a diffuse central spot of silver, and purple beneath, studded with bright rose-pink flowers. It also spreads, but not as widely as O. oregana. It is evergreen and keeps a neat appearance all winter.
Omphalodes verna (Blue eyed Mary), is an uncommon shade lover with low growing elongated heart shaped leaves of mid-green and 6” clusters of flowers reminiscent of Forget-Me-Nots in size and intensity of true blue. This plant spreads by runners, rooting at the tips as it goes, eventually becoming a loose mat just a few inches high. It blooms in early spring for about 6 to 8 weeks. For a pretty combination try combining O. verna with yellow, cream, or pink Erythronium. The Erythronium easily come up through the loose mat of Omphalodes and bloom at the same time, creating a charming garden picture.
Gaultheria procumbens has smooth shiny oval leaves about 3” long and 1” wide. It is perfectly evergreen and spreads at a nice pace to make a solid cover about 6” high, excellent under shrubs such as rhododendrons. It is related to rhododendrons and thrives under the same cultural conditions. The clusters of small pale pink urn shaped flowers give way to long lasting large bright red berries. The flavor and smell of the crushed berries give it the common name of Wintergreen. It is native to the East Coast of the USA.
Wild ginger is another option to consider . Our nativeA. caudatum is a fast and wide spreader when happy. It has mid-green heart shaped leaves that lie almost at ground level, and curious brownish red flowers nestled beneath the leaves, but worth looking for. The roots and rhizomes of this plant smell and taste strongly of ginger. A. europeum, European Wild Ginger, is perhaps an even better groundcover choice. It has shiny, thick, dark green, heart shaped leaves, and is perfectly evergreen. It spreads, but not as quickly, and it’s neatness of habit and density of growth make this one a favorite.
Groundcovers do not necessarily have to be spreaders. Consider an underplanting of hosta or pulmonaria. Hostas are deciduous shade lovers native to Asia, and are quickly gaining favor for their hardiness, longevity and the multiplicity of forms available. Hostas form neat rounded clumps of big, bold, lance to heart-shaped leaves of varying shades of green. There are an abundance of striking variegated forms, with streaks or splashes of gold, creamy yellow, or white, especially effective in brightening up a shady spot. Hostas are exceptionally long lived, becoming more impressive each year. There are varieties that rise no more than 2“ off the ground and 4” across, to giants over 3’ high and 6’ across. A planting of hostas under a tree or along the shady side of a building will quickly fill in to create a weed smothering groundcover. Local nurseries are now stocking a wide selection, and if that is not enough to satisfy, hundreds of cultivars can be found at some specialty nurseries.
Pulmonaria (Lungwort) is also enjoying renewed popularity. Low growing and clump forming, pulmonarias are excellent groundcovers when planted ‘en masse’. They have elongated, broadly sword shaped leaves, some up to 2’ long and lying flat, some a mere 8” and somewhat upright. They are commonly a deep rich green with varying degrees of showy silver spotting on the leaves, with the rough texture typical of most plants in the Borage family. The sprays of small flowers are usually of some shade of clear blue, blooming in early to mid-spring. Some varieties have flowers with the interesting trait of emerging pink and changing to blue, so that pink and blue flowers share the same plant. There are also white flowered forms. New varieties are being bred for mildew resistance, heavy silvering of leaves, (P. ’Ex Caliber’ is almost pure silver), abundance of flower, and undulating leaf edges. P. longifolia ‘Bertram Anderson’, P. ‘Roy Davidson’, and P. ‘Ex Caliber’ are all excellent choices. They are semi-evergreen, only losing their leaves completely during the coldest winter.
Another plant, not usually thought of as a groundcover, but which suits the role perfectly, is Helleborus orientalis (Lenten Rose), now more correctly considered H. x hybridus. These plants have large, shiny, thick, dark green leaves deeply divided into 5 or more leaflets. They are evergreen, grow to about 2’ tall, and each plant will cover a space about 3’ x 3’ after a few years. Depending on the form, they start to bloom in late winter to early spring. What we see as petals are actually the sepals, and, fading slowly, will hold their ‘bloom’ for a very long time, sometimes up to 2 months. The nodding cup shaped flowers are about 2” across and grow in clusters just above the foliage. They can be white, pinkish or deep purple and are frequently finely spotted. Much hybridizing and selecting is being done for flower form and color, mostly in England and Germany, and hopefully we will soon have improved forms to choose from. But for groundcover effect alone, the flowers are a bonus, incidental to the rich green foliage effect. Good displays of H. x hybridus can be seen at the Berry Garden.
There are many more possibilities. Consider a planting of ferns. Our native Sword Fern is still one the best, although there are so many choices it is hard to choose a favorite. New Heuchera varieties (Coral Bells) with robust leaves overlaid with purple and silver will overwinter as tidy clumps, expand with luxurious foliage in spring and bloom most of the spring and summer. Spreading woodland phlox (P. stolonifera) will also do the job.
So let your imagination loose. Get ideas from the local Botanical gardens and from the display gardens of the numerous specialty nurseries in the area. Seeing the plants in a garden setting is a world apart from seeing them in small pots on the nursery sales table.
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STALKING THE WILD VARIEGATION
I didn’t see it immediately. In fact I passed it right over as I concentrated instead on the Spiraea betulifolia growing on the gravely hillside along the mountain path that hot sunny morning last summer. I admit I completely missed it, until my sister-in-law so casually remarks, “Oh, look, a variegated one”. What!? So nonchalant was she, she could have had no idea that the green, white, and gold streaked Smilacina racemosa that she was referring to would subsequently elicit such a reaction from me. Yes, I was excited, (and admittedly a little disappointed that I did not see it first). The Smilacina had only one stem, about 2’ tall, but it was perfect - strongly and irregularly streaked with green, white, and gold, much like a hosta that has not yet settled into it’s final variegation. Now this lovely specimen is residing in our garden, with still only one stem after a year, but alive and well. I had a few bad moments as it emerged green this spring, but as the season progressed, the variegation brightened, first to gold and green, and now, in early summer it has more white streaking, much like it was when I first saw it.
Everywhere we go, we look. It is a hunt and one never knows what one will find. Consider the case of the variegated Vancouveria hexandra . When I found this one in a nearby woodland, it had one stem with a few leaflets with strange white and grayish markings. Thinking it was probably one of those frustratingly fleeting, here-one-year-gone-the-next variegates, I did not get too excited about it, but one never knows, so I brought it home and stuck it in the rear corner of one of our greenhouses, in the section reserved for ‘oddball plants to watch’. This year it has many stems with leaflets of the oddest distinctly separated green, gray, and white patches, somewhat distorting the leaf shape because of the different growth rates of each section, but quite strong and healthy, and strangely attractive. Now that it is planted in the garden it is starting to clump up and I expect that it be running around shortly. The three similar forms we found in the redwood forest this summer look like they may be good also. We will see, but they are very small, and may not hold the second year.
Of course, the hunt need not take one to far away places. The variegated bull thistle came from the field behind our house, and now it has a prime spot in the garden, fitting right in with it’s lovely spiny foliage of green and bright gold. It has a place of honor in our variegated weed section, near the Plantago major ‘Variegata’, the gold streaked dandelion, and the white mottled clover. So we just let them laugh when they come, these unenlightened garden visitors, and we smile to ourselves, because we know things they do not.
And the gold streaked Paeonia mlokosewitschii is quite nice too, but was hardly any hunt at all. All we did was look down in the flat of seedlings, and there it was.
Now I am looking for a variegated Smilacina stellata, a lovely plant in it’s own right that forms a dense groundcover when happy. Any variegated form will do. I expect to turn a corner of a trail one day or to be scrambling through some obscure woodland underbrush, and come upon the perfect variegated patch, rivaling the lovely Disporum sessile ‘Variegata’ in effect and vigor. It could happen. But finding these gems is a rare occurrence and always comes as a surprise. It is a hunt, an unknown, and that makes it all the more exciting when it happens.
So next week we are off to the woods again, or maybe to the mountains, to see what we can find. A streaked Skunk Cabbage (Lysichiton americanum) perhaps, or a gold splashed Devil’s Club (Oplopanax horridum), or any Carex that grows by the hundreds of thousands in any marshy spot along the way. We know they are out there, and the hunt is on.
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