Companion Plants in the Rhododendron Garden, Part 1

Acer x 'Sugarflake'

I lament that I didn't have the brains to be a botanist, to readily answer the question about the difference between petals, tepals and sepals, for example – some plants seem to have them all – or why Pinus thunbergii is now deemed to be Pinus thunbergiana. Nobody ever invites me to a botanical congress, nor do botanists give credence to the possibility that Acer griseum can hybridize with Acer saccharum, even though I grow such a cross (Acer x 'Sugarflake').

Watering nymphs?

The Greek word botane is from bosko for “feed, tend or nourish,” and was basically “pasturage” to the early Greeks, and later it would mean “weed” or “herb.” The adjective botanikos was “of herbs,” then eventually botanicus referred to the study of plants. Chloris, from chloe – the first green shoot – was the Greek equivalent to the Latin Flora. Chloris was the definition of spring and was the goddess of flowers. The nymphs of the springs were in charge of the plants and made sure that the landscape received adequate moisture from Oceanus, the father of the rivers. So far I am unable to find toga-clad nymphs to tend  to my plants, and I am afraid that most would dry out and die if I didn't administer watering instructions daily.

In any case I feel fortunate that I can visit a world-class botanic garden – the Rhododendron Species Foundation – which is located relatively close to my home, about three and a half hours away. I have been there twice already this spring, and I plan to visit every three weeks until summer, and then at least once again in the fall. I've never encountered nymphs tending to plants there either, rather hard-working men and women with dirty jeans and sweat on their brows. The garden contains a world-class Rhododendron collection, but even if that genus did not exist you would still have a world-renowned collection of maples, magnolias, ferns, lilies and much more.

Meconopsis 'Lingholm'

So let's forget about their Rhododendrons then, and we'll focus on all of the other stuff. The garden is famous for a large patch of Meconopsis 'Lingholm', and though they are not in flower yet, the new foliage is up and scattered over a large area. The “Blue Poppies” are considered rather difficult to grow in most American landscapes, for they prefer cool summer temperatures and mild winters, but this Federal Way, Washington botanic garden seems to be the perfect location. 'Lingholm' is a hybrid perennial poppy that was discovered in 1996 at Lingholm Gardens in northwestern England. Its parents were M. betonicifolia (Tibetan blue poppy) and M. grandis (Himalayan blue poppy). Meconopsis is not a true poppy – Papaver – but the generic word is derived from Greek mekon for “poppy” and opsis for “appearance,” due to their similarity.

Cardiocrinum giganteum var. giganteum

Cardiocrininum giganteum var. giganteum

Cardiocrinum giganteum var. giganteum seeds

Nathaniel Wallich

Mingled amongst the Meconopsis are a number of Cardiocrinum, and two plants were already five feet tall with lush full-sized leaves. Species giganteum is commonly known as the “Giant Himalayan Lily” and it can produce numerous trumpets atop a stem up to twelve feet high. Blossoms of giganteum variety giganteum are greenish white on the outside, and on the inside they are streaked with purple. A color breakthrough has been achieved by Far Reaches Farm in Washington state through wild collection, and we now grow one of their pink seedlings. It might also flower pink, or perhaps it will be the normal white, but then it could possibly flower red. Cardiocrinum was originally introduced into Britain in the 1850's as Lilium giganteum, and was first scientifically described by Nathaniel Wallich from plants in Nepal. Wallich was a Danish surgeon and botanist who worked for the East India Company, and who was involved in the development of the Calcutta Botanical Garden. I visited said garden in the late 1970's where I sweated gallons in the summer humidity and found none of the palms (etc.) to be of any interest. What was of interest were the young upper-caste Indian girls in their expensive saris, but they pointed at me and giggled...

Cercidiphyllum japonicum in Fall 2014

Cercidiphyllum japonicum in April

Cercidiphyllum japonicum 'Pendula'

Cercidiphyllum magnificum

The sun would come and go on this early April day, but at one moment it lit up the garden's huge “Katsura,” Cercidiphyllum japonicum. Today the foliage was twinkling lime-green in the sun, but I remembered last fall when it was straw-yellow. It's great that they allow enough space to accommodate this majestic specimen for I only grow smaller cultivars, but they too grow pretty big. The photo of 'Pendula' above is a memory of a specimen in my Display Garden, but the tree grew too large and was edited from the landscape. Cercidiphyllum was so-named due to the resemblance of its leaves to genus Cercis. There are two species: 1) japonicum from Japan and China – the larger of the two – and 2) magnificum, the smaller, usually reaching no more than 30' tall. If you hand me a leaf from each I would be unable to tell you which species is which. But then, again, I am not smart enough to be a botanist.

Sorbus sargentiana

Sorbus sargentiana

Charles Sargent

Near to the Meconopsis/Cardiocrinum patch is a glorious tree that I have seen nowhere else: Sorbus sargentiana, or “Sargent's Rowan Tree.” Sargent, of course, was an American botanist and  the first director of Harvard University's Arnold Arboretum, and he held that post (for 54 years) until his death in 1927. I have been to many English gardens – or I should say Gardens – where the “rowans” are popular, but I have never encountered S. sargentiana before*, except at the Rhododendron Species Foundation. In early spring the emerging foliage is a delicious ruby-red-brown, and the spring sun can light it – delight it – up beautifully. This species was introduced in 1908 from China by plant collector E.H. Wilson who worked for Sargent at the Arnold.

*Here is where I'll admit my ignorance, for while I have never seen Sorbus sargentiana in an English Garden, I guess I was visiting at the wrong time or for some other reason. Sargent's rowan was awarded the RHS Award of Garden Merit for its bold foliage – with leaves the largest of any Sorbus – and for the bright orange-red-to-red fruits in autumn. In Washington state I remember that the leaves had turned to purple-red by the end of October, so we have a great small to medium-size tree that I would love to acquire.

Adiantum venustum

Let's get to the ferns, for many species thrive in the humus-rich soil under the tall native Pseudotsuga menziesii. I don't know much about ferns, so I pulled Sue Olsen's  Encyclopedia of Garden Ferns off the shelf for assistance. One encounters Adiantum venustum upon entering the Rhododendron garden, and as Sue writes, “the maidenhairs are popular and beautifully irresistible.” She continues that “Adiantum comes from the Greek adiantos, which means “to shed water” or “unwettable” and refers to the water-repellent characteristic of maidenhair foliage.” You should buy her book, for you'll be treated to accounts such as “In flight the maiden tumbled over a precipice catching her black hair in the bushes where the hair took root and sprouted into our familiar fern.” God, I love the thought of tumbling maidens. Moreover, I learn from Sue that venustum is an epithet meaning “graceful” or “beautiful,” which is derived from Latin venustus for “charming” or “elegant.” A. venustum, the Himalayan “maidenhair fern,” is hardy to USDA zone 5, or minus 20 degrees, and has been referred to as a “gentle” groundcover.

Dryopteris sieboldii

Philipp von Siebold

Less “gentle” is Dryopteris sieboldii, or “Siebold's wood fern,” and I can think of no other fern even close in resemblance. According to Sue, this species is “found in the drier forests of Japan, China and Taiwan,” but it seems to be very happy in the wet environment of Washington state. Dryopteris is from Greek drys for “oak” or “forest,” and pteris for “fern,” while the specific name honors the German Phillipp von Siebold (1796-1866) – no stranger to the Flora Wonder Blog – who studied and collected plants in Japan.

Osmunda cinnamomea

Blechnum chilense

Matteuccia struthiopteris

Osmunda cinnamomea was at an interesting stage of development, with its young silvery stems and heads arising. Blechnum chilense – from Chile of course – was not yet displaying new reddish fronds, but was entirely green. Sue explains that “Chileans call the unfurling fronds costilla de la vaca, 'ribs of the cow.'” How I wish that I had a porter with me to carry Sue's fern book and other plant books as I walk through this botanic garden. I suppose the most impressive of the garden's ferns is a huge gathering of Matteuccia struthiopteris, the “Ostrich fern.” The genus is named for the Italian Carlo Matteucci (1811-1868) and the species is named from struthio for “ostrich” and pteris for “fern.” Sue says that “plantings can become quite invasive but if you do not want them, you can always eat them.” Also “Ostrich fern is the state vegetable of Vermont and largest export crop of New Brunswick, Canada.”

Agapetes lacei

Agapetes lacei

Agapetes 'Red Elf'

Agapetes 'Red Elf'

Moving away from the ferns – and hopefully without the publisher suing me for plagiarism – I entered the fancy conservatory, home for many tender Rhododendron species. But there are a lot of other gorgeous plants as well. I was intrigued with a basket with a pretty Agapetes lacei, as if growing as an epiphyte. The new growth was pink while the older leaves were green. Further research reveals that the specific name could be lacie, but obviously I don't know which spelling is correct. My limited experience with Agapetes was from walking through the Himalayan foothills with it (A. serpens) festooned on the branches along the trail. Small red flowers were scattered on the trail – which I noticed first – and I wondered if nearby children had beautified my path in anticipation of my visit. Years later I ordered via mail Agapetes 'Red Elf' from a Tasmanian nursery, knowing full well that it would not be hardy for me outside, but I visit it frequently in my GH20 hot-house. Besides, I like the fact that the Greek word agapetes means “beloved,” and also that the plant reminds me of my youthful capers in the Himalaya.

Primula denticulata

Primula denticulata 'Ronsdorf'

Also native to Himalayan foothills is Primula denticulata, the “drumstick primula.” The “Ronsdorf” hybrids are a strain of seedlings that can vary in color, but they're all pretty nice. Most Primula species occur in Asia, from 5,000' to 14,000' in elevation, and all they require is an area that retains moisture, and can even thrive in a boggy ground. The word primrose is from Latin prima rosa meaning “first rose,” since most species bloom in early spring. Georg Ronsdorf (1863-1952) was a German breeder from Ronsdorf, Germany, and was considered one of the most important perennial breeders of the 20^th century. Sadly for the flower man was that WWII air-raids nearly destroyed his life's work.

Styrax perkinsiae

I encountered a scraggly Styrax perkinsiae in the garden, but it was my first encounter with the species and I know very little about it. I think it was discovered by E.H. Wilson in China in 1912, then left to Rehder and Sargent of the Arnold Arboretum to cubby-hole further. One can easily dismiss this shrub-to-small-tree as merely a BIO Plant – Botanical Interest Only – but the real brains of the world recognize that Egonol gentriobioside and Egonol gentriotrioside – look carefully at the different spellings – from Styrax perkinsiae promotes the biosynthesis of estrogen by aromatase. For real people – not scientists! – estrogen deficiency is associated with a variety of diseases, such as osteoporosis, atherosclerosis and Alzheimer's disease. Yikes! – that sounds horrible, and please tell me what to do: to chew on this tree's bark, or to make a tea, or to just lie-down next to it? I am certainly no match for science – just tell me what to do! Does my wife need any? So what that Egonol gentriotrioside was also found to increase the serum level in ovariectomized rats. Really, humans never want to be compared to rats, or to acknowledge that the study of rats has anything at all to do with us...people.

Dysosma pleinantha

Moving along I came to a luxurious patch of “May apples,” the genus Podophyllum, but the label indicates that it is Dysosma pleinantha. Great, once again the botanical world has shifted while I was unaware. It turns out Dysosma is the Asian version while Podophyllum peltatum is the eastern American wildflower, the latter a plant I think I've never seen. Leaves of the American genus are dissected nearly to the center, while the Asian genus has round leaves that look like old tractor seats. Surprisingly, both genera are in the barberry family, Berberidaceae. Everyone is impressed with our huge clump of the variegated 'Kaleidoscope', which I guess is also a Dysosma. My start came from a company that has no interest in botanical accuracy, and I am left to wonder if it is a hybrid or not. The idea of using an x would be simple, and maybe let us know which parents were involved.

I quit the Rhododendron Species Foundation in the early afternoon, my body tired from battling the brush  to find the labels, and my brain overwhelmed with new plants as well as some old favorites. It's almost seven hours of driving to make the round trip, while I spent only one and a half hours in the garden. Call me crazy, but for me it was worth it.

Rhododendron 'Alpine Glow'

I promised no Rhododendrons in this blog but I can't resist to show it: I saw a plant glowing in the distance, but I had no idea what it was. Upon closer inspection I realized it was a Rhododendron, and the label said 'Alpine Glow'. That is a R. 'Loderi Group' - which is a R. grissithianum x R. fortunei ssp. fortunei - crossed by R. calophytum var. calophytum. I know: TMI. Anyway, stay tuned for Part 2 of this incredible garden.