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Archive for February, 2011

ORNAMENTALITY  (Originally published in the ARS NY Chapter Newsletter around 1990.  It is somewhat dated.)

Ornamentality is what we are looking for, or at least should be looking for as rhododendron hybridizers. Not just new rhododendrons, ones that are tough, somewhat compact growing, and bloom unfailingly year after year but especially highly ornamental – those that are beautiful when they bloom and when they don’t bloom.

Where are we going to find these new plants? To get a clue, why not look at what other successful hybridizers have done. Far and away the most successful Eastern hybridizer was Charles Dexter. The Dexter hybrids are what the average person thinks a beautiful rhododendron is. What was the basis for his success? – rhododendron fortunei. It is gorgeous, fragrant, and a consistant bloomer. It is also a tall growing, leggy plant that usually is not very hardy.

We have a great advantage over Mr. Dexter because not only do we have a very hardy form of rh. fortunei,we also have the hardy form as a parent in hybrids. Of course, we also have Mr. Dexter’s own hybrids.

Cecil Smith’s ‘Nestucca’ – yak x fortunei – is certainly a place to start if you want dense growing whites. There are other yak x fortunei hybrids available too but ‘Nestucca’ is certainly beautiful. Dexter’s ‘Gi Gi’ et al (‘ripple’ and ‘Lady L’) could be a starting point for reds – especially indumented ones as it is reputed to be a haematodes hybrid and haematodes is almost as indumented as yak itself.

Hardgrove showed that hardy fortunei transmits the yellow color of a pollen parent to the progeny along with fortunei’s hardiness. ‘Golden Star’ or ‘Donna Hardgrove’ could be the start for yellow and orange hybrids. ‘Donna Hardgrove’ is quite hardy and not a leggy grower. It is very orange-yellow. Even though these are quite yellow, the flowers have long pedicels and you don’t get a tight, full truss.

We are beginning to see that smirnowii is giving hardy yellow hybrids when crossed with yellow – ‘Hello Dolly’ for example. Why not cross these yellow smirnowii hybrids with the Hardgrove yellows?

Let’s get back to what the public thinks an ornamental hrododendron is. The public wants a reliably bud hardy plant that can be planted anywhere, given no special care, will produce an enormous number of flowers on a fairly compact plant year after year and will not be damaged over the winter. The public wants a lot of bang for the buck and no excuses.

The trend of some contemporary hybridizers is for odd ball hybrids, plants that have no hope of performing in the nurseryman’s field or the garden of a non rhododendron enthusiast in the Northeast. These are conneseur rhododendron – meant for a market of perhaps 200 growers nationwide.

It is of meager value to develop a plant that blasts two out of three years, even if the one year it is super. It is of no value to develop a wide open growing leggy plant that is 10 feet tall in as many years no matter what the flower is. One of our problems is truss shows. Someone climbs a 10 foot ladder to cut the closest – to – the – ground (and only) truss to enter in the show. People see this beauty and immediately demand it be named and propagated after it wins “Best New Hybrid”. It is, of course, really a dog.

We are all going hither and dither making crosses for rhododendron connoisseurs – really I suspect, because they are the ones who are judges and tell the hybridizer how great he is. They are also the people who give Gold Medals to hybridizers. No one is hybridizing for the masses. Not only is it such a simple thing to do but you also get a good proportion of seedlings that are beautiful. Just use any of the Dexters as parents – ‘Scintillation’ is a wonderful mother. (It has no pollen, so it can’t be a daddy). With a yellow pollen parent many of the offspring are yellow and yellow-pink. With a red parent, the offspring are dark pink to blue red. ‘Janet Blair has probably the best reputation as a seed parent among the Dexter rhododendrons.

Many sophisticated rhododendron collectors turn up their noses at the blue-red color we see so often in Northeast hardy rhododendrons. This business of blue-red unattractiveness gets a little silly. The masses think that blue-red rhododendron are gorgeous. It is a few enthusiasts who keep talking them down. The influence that a few have had in this respect is phenomenal.

I’d love to cross ‘Scintillation’ with any of the west coast monsters – ‘Wallaper’ et al for example. Since ‘Anna’ has produced so many wonderful hybrids, why not use it on ‘Scintillation’. (‘What does ‘Anna’ have that produces such offspring? I never see ‘Wallaper’ used in hybrids. Is it because it is sterile? If it is, it would add to my suspicion that it is a triploid. Maybe ‘Anna’ is a tetraploid.)

Please remember that what the general public thinks is ornamental is a Dexter type plant – tough, gorgeous and easy to grow and propagate. Shoot for those goals. Start with a Dexter or similar hybrid and go forward – at least two generations keeping colors separate (cross red to red, white to white, etc.). Remember the hybriders credo: If you have to make any excuses for a hybrid of yours, its not good enough.

(As published in the ARS Journal, Winter, 2011

Now that we are ending the first decade of the 21st century, I thought it might be useful to step back a little and try to look at rhododendrons and how they fit into current society.  In 2012 I will celebrate (?) my 50th year anniversary of joining the ARS and growing rhododendrons, so I thought it would be useful personally for me too.

We should start by looking to see how things have changed in society over these last 50 or so years.  There have been remarkable changes in the way we live, in rhododendrons and in how people interact with these plants.

The most significant changes in how we live are in electronics.  Black and white television gave way to color and now high definition screens.  Magnificent color pictures displayed on 102 x 76 cm (40 by 30 inch) screens with the clarity of a perfectly printed color photograph.  Cable and satellite connections allow the viewer to choose from hundreds of stations or to select from a catalog of movies to view “on demand” in their home.

The personal computer started out as a semi-toy not able to do much, but now with its enormous storage capacity and speed they are almost a requirement for the home.  Of course connection to the internet is the enormous benefit of the PC.  It allows a user to communicate with people all over the world and to access information on any subject almost instantly.

Immediacy is an apt description for current society.  No one wants to wait for anything.  People have done without an item for years but now when they suddenly want something, they must have it NOW.  At fast food restaurants, you can have a complete meal delivered in two minutes.

Cell phones, a miracle ten years ago, have become blackberries, I-Pods and I-phones.  All of these devices have become commonplace and are now a part of daily living.  No one now even considers how miraculous they are.

Well how do all these electronic features of our current way of living affect rhododendrons?  Remarkably!   To put it succinctly, rhododendrons must compete with these modern electronic devices for the attention of people, and most of the time the plants lose. The desire for immediacy finds itself in rhododendrons too.  No one wants small plants that you will have to wait three or so years for to see a flower.  Everyone wants to buy plants with flower buds.

Around 1970, membership in the New York Chapter skyrocketed.  We used to have an information booth and display garden at the International Flower Show held each year at the Coliseum on Columbus Circle in New York City.  One year alone, we took in 150 new members, and we had 450 members in our chapter.  And we were not alone in having large active memberships!  All plant societies, clubs and civic groups were loaded with members.  Most had waiting lists for membership.

This was 25 years after the end of WW II.  Returning veterans who had purchased homes in 1944 and 1945 now found themselves with spare time and an improved financial situation.  Children had left the home, mortgages were paid off or were so small to be inconsequential and they had progressed in their jobs and careers.  There was very little competition for their spare time, so hobbies abounded, especially horticultural hobbies.

But by 1990, things started to change.  All those people who joined the ARS back in 1970 were now retiring.  That home that cost them $5,000 or $6,000 back in 1945 was now worth $250,000 – $300,000.  Taxes on the home had gone from about $100 in 1945 to $5,000 to $6,000.  With fixed incomes, those taxes looked threatening and the house value looked inviting.  They began to cash out, selling the home and moving to Florida, Arizona, North Carolina or somewhere where living was easy and inexpensive.  ARS chapter memberships began to fall.

The people who moved into these homes had life styles completely different from those who moved out.  They were electronically sophisticated with all the electronic gadgets, the PC, I-phone, Blackberry, HD TV etc.  A big mortgage on the home together with the high taxes added to their requirements for income.  In order to afford this life style, both husband and wife had to work.  Their days and evenings were filled with all sorts of things that had to be done.  What little free time they had was devoted to the internet or television.  After working all day and not getting home until 6:30 or 7 PM, they had very little time for meetings of any sort, including an ARS meeting.

But there was something else holding them back from joining any plant society.  You see the seemingly simple life of growing rhododendrons is completely alien to their speedy, sophisticated life style, so that they just could not comprehend themselves getting involved in a horticultural club, any horticultural club. Some young people have told me that horticulture is “so retro” or “so 1930”!

So that is what we are facing now, a culture that is very busy and super sophisticated using all kinds of gadgets to occupy all of what little spare time they have.

So as you can see, society has changed, but so too have rhododendrons. Just about 50 years ago, nurseryman started experimenting by growing rhododendrons in containers.  That has progressed to the point now where virtually all commercially produced rhododendrons are sold as containerized plants.  This mode of production has enormous advantages for the nurseryman.  By selecting suitable cultivars he is able to produce in two years a plant that would have taken five years to grow in the ground the old fashioned way.  Costco was selling rhododendrons in 11 l (three gallon) pots for $US 19.95 this spring.  I counted 40 flower buds on one of the plants.  The cultivars being offered were ‘Roseum Elegans’, ‘English Roseum’, ‘Catawbiense Boursault’ and ‘Nova Zembla’.

I have written in the past of my opinion of these containerized plants, so I will not revisit my concern with them2. Someone in the rhododendron group chat room on the internet called these “plants on steroids”, which I think is a good description. These plants, purchased in the spring, must be watered every week until late fall and it wouldn’t hurt to watch them next year for any signs of desiccation and to respond appropriately. The problem is that the purchaser is not told of the weekly watering requirement of these plants. But I am told that without containerization, there would be no rhododendrons available to the general public, which I guess is true.  This means that hybridizers now must not only have unique, hardy hybrids but the plants also must have to respond perfectly to container growing.

The other new feature for rhododendrons, at least in Northeast America, is the increase in the number of deer.  Bambi might be a beautiful animal but she can really destroy rhododendrons.  Nature kept the deer population in check with bears and wolves, both of which are gone, at least where I live. Hunting, which is really the only way to keep the numbers down, is not permitted anywhere near homes. You can not grow rhododendrons where there are deer unless you erect a three metre (10’) high fence all around the property or have a large dog stationed outdoors at night.  Stores sell deer repellents, but I am told they are not very effective.

Probably the most exciting new feature with rhododendrons, which fits right in to modern society and electronic gadgetry, is the internet group or chat room1. It is extremely valuable and using it, you will learn a lot and be able to help others with questions or problems.

The situation with hybridizing the genus is terrific.  There are several active hybridizers in the East, all with many beautiful hybrids in their gardens. I know I’ll get many people angry at me to say this, but it is really easy to hybridize rhododendrons and get beautiful seedlings.  Just cross two Dexter hybrids. Cross ‘Janet Blair’ with any good hybrid and you will get plants with beautiful flowers.  They probably won’t be too different from those we already have, but you will be the proud parent of some great plants. Of course you will have to wait five or six years to see flowers, which flies in the face of the desire to see immediate results.

But nobody is propagating these great plants in hybridizer’s gardens.  There are very few rhododendron specialty nurseries, so many hybridizers propagate their own plants now and give them to friends or offer them for sale at chapter plant sales.  There is no easy source for purchasing new hybrids from hybridizers who are in different chapters.  Many hybridizers hold back their plants, concerned that their name might be associated with a hybrid that, in the long run, turns out not to be too good.  So they want to test the plant in their own garden for several decades.  I do respect that thought, but I fear many good plants will be lost upon the death of the hybridizer.  I personally don’t name plants, I just number them to identify them and make them available to anyone who wants to grow them.  If sometime in the future  wants to name and register the plant, they are welcome to do so.

Also thrown into the mix is the “no more room” factor.  Many of our members have been growing rhododendrons for a long time and have an extensive collection of cultivars.  They have run out of room in their gardens for more plants.  To add a new plant requires that an existing plant be removed and it can be difficult to decide which plant must go.  I know of garden where its owner had collected all the newest, best hybrids back in the 60’s and 70’s and had a fabulous garden, a must see on any garden tour.  He stopped collecting because he had no more room and couldn’t get rid of any of “his children”.  Over time, those newest, best hybrids didn’t turn out so well.  Remembering the effort he put into acquiring the plants, he just couldn’t get rid of any. So he ended up with a collection of overgrown, ho-hum plants that didn’t compare with what is available now in the 21st century. The garden became old, outdated and uninteresting.

I can remember back in the late 60’s a new plant was named ‘Ben Mosely’.  Everyone wanted it. It had a flawless reputation: beautiful, large truss, great foliage and leaf retention that gave the plant a dense, full appearance.  I was able to beg a cutting of it.  I rooted it and after a few years took cuttings of it and ended up with 5 or 6 plants.  Well after 35 years the plants were enormous and took up a third of my front garden.  The cultivar that was at one time so revered and desired had lost its glow.  Last spring I cut all but one down to make room for new cultivars.

In the good old days, people seeked out and found the ARS chapter and became members.  Now things have changed 180 degrees. We must go out and find the people.  Even though I have written in the past of my “unease” with rhododendron flower shows, the show is an easy and direct way to attract members3.  Visitors who seem very interested in the entries, or who ask a lot of questions at an information booth should be approached and asked about membership.  An offer to visit the garden of someone who is having a problem with their rhododendrons is a great way to break the ice and get them interested in membership.

Giving talks to garden clubs and civic meetings is another way to introduce the gardening public to rhododendrons.  The important thing is that we must do something. Sitting back and doing nothing is inviting slow death.

There is something that the ARS offers members that is not found on the internet, HD television, the blackberry or I-phone.  That is interaction with real people, nice people, in person with no electronics between them. And this is what we must stress.

Our goal should be to integrate the study and growing of rhododendrons into our sophisticated society so that people can see that there is as much a challenge in being successful with these plants as there is in most other challenges they encounter.

1 .  Just go to WWW.YAHOO.COM. Go to group, then type in “rhodo” and away you go.

2 Journal of the ARS, Vol 51, #3, Page 145

3 Journal of the ARS, Vol 60, #2, Page 70

The Ironclad Rhododendrons

Lest we forget—the Past is Prelude

RICHARD MURCOTT the New York Chapter

Published in the NY Chapter newsletter about 1990.

We now hear very little about a group of hybrid rhododendrons that, when I started collecting and growing this genus in 1962, were the mainstay of the plants available. The Dexter Hybrids were very sparingly available, really just sold as a favor to the purchaser. There were other cultivars available, but the basic selection of rhododendrons available in garden centers were the Ironclads.

To understand where they came from and how they were designated, a little history is necessary. Rhododendrons started to be hybridized in England in the early 1800’s. The English had by this time obtained seed and plants of a few species native to Europe, the Caucus mountains and the American species catawbiense and maximum. When the English saw the blood red flowers produced by plants grown from seed of the Asian species they went gaga. Their blooming about 1850 started a hybridizing frenzy. Many hybrids of ponticum, caucasicum, catawbiense, maximum and arboreum were created.

The Centennial Exhibition of American Independence was held in 1876 in Philadelphia. It was there at that exhibition that the American public first came to see hybrid rhododendrons as 3,000 hybrids were brought in from England and used throughout the grounds as landscaping plants. They were immensely popular. These plants were sold to local gardeners in the Philadelphia area at the end of the show and I don’t doubt that some of them or propagations of them are still growing there.

Nurseries began to get many inquiries regarding hybrid rhododendrons. This started a 50 year love affair for these plants, mainly by the wealthy as the plants were very expensive. Many nurseries began to import plants and soon it became evident that not all hybrid rhododendrons were both beautiful and hardy. The enormous variations in the climate on the East Coast made selection of cultivars frustrating. A plant perfectly hardy in Philadelphia would succumb to the cold during its first winter in Boston. This feature was not lost to the Arnold Arboretum. They had imported many named hybrids from Anthony Waterer and had discovered the remarkable variability of the plant’s hardiness.

After many years of observing these plants growing at the Arboretum, and with consultation with nurserymen also growing them, E.H. Wilson, in 1917, published a list of “Ironclad Rhododendrons.” The original list consisted of fourteen cultivars. The “Ironclad” referred to their ability to withstand severe winter conditions. This list is appended to the end of this article. In 1927 the list was shortened to twelve and became known as “Wilson’s Dozen” or “the ironclads”.

The publication of this list had many lasting effects on rhododendrons. First, it made everyone aware that rhododendrons varied in their hardiness and that proper cultivar selection was most important for success. Second, even though the title didn’t say so, everyone thought that the cultivars on the list were the only hardy rhododendrons. This was certainly not so. They were the hardiest of the plants imported from Waterer! There were certainly other hybrids from Holland, Germany and yes, even America. (The Parsons Nursery in Flushing had named several very hardy hybrids) that equaled their hardiness. And lastly, it permanently placed the Waterer name to the top of the list of important rhododendron hybridizers. Once again, this shows that someone other than the hybridizer is usually responsible for the placement of the hybridizer in the history of rhododendrons. (Another fact to remember is that the embargo prohibiting the importation of plants with soil on their roots was enacted about 1917. That effectively cut off the importation of newer European hybrids that might have competed with those on the ironclad list.) If it weren’t for the publication of this list, I wonder if anyone now would know the name of Waterer!

Of course, asexual propagation of rhododendrons in the early 20th century was very slow. Grafting or layering were the only two ways available. They both had drawbacks. Grafting suffered from understock growth, understock compatibility, and required highly skilled personnel to be successful. Layering took at least a year and could only be done every third year to the same plant. Even though propagation was slow, with the passage of time, rhododendrons were roaring in the Roaring Twenties.

There are a relatively small number of individuals who really had an enormous impact on rhododendrons. One such person was Paul Vossburg. Paul developed a love for the plant while working at Hicks Nursery from 1917 to 1942. During the war, when he was working at an aircraft factory, he developed a technique to root rhododendrons. He perfected the use of indole-3-butyric acid that Professor Zimmerman at the Boyce Thompson Institute discovered in 1939.

After the war Paul worked for Westbury Rose propagating rhododendrons by the tens of thousands, an unheard of feat in that day. What cultivars was he propagating?—the Ironclads, of course. He knew of many large plants on the north shore of Long Island from which cuttings could be taken. (He, by 1950, had become a member of, and the propagator for, the Dexter Committee too, but that is another story.) I guess that the heyday of the Ironclad was just about when I started in 1962. Westbury Rose must have had 100,000 of them growing in their nursery. It was really all that was available in retail nurseries.

What happened to them, you ask? Dexter is what happened. There aren’t too many sensible people going to grow an Ironclad when they can grow one of Mr. Dexter’s hybrids. Over the last thirty years, the Ironclads have disappeared on Long Island and really anywhere that the climate allows the Dexters to be grown. I doubt that a complete collection of Ironclads exists today in a private garden. I do think that ‘Mrs. C.S. Sargent’ is one of the best of the Ironclads that even stands up to a Dexter, and I would encourage anyone to grow it, if you can find it.

Space, and my knowledge of the subject, does not allow me to talk too much of the experience hybridizers have had using the Ironclads. Clem Bowers, another giant in the history of rhododendrons, was one person to extensively use the Ironclads. He wanted to create hybrid rhododendrons hardy in the Binghamton area of New York State where the winter temperatures go to -40°. Since the Ironclads were the hardiest hybrids we had, he thought that he would cross each of them with each other of the Ironclads. So in 1926 and 1927 he made the 196 crosses and gave the seed to Hicks Nurseries in Westbury to grow on. The devastating winter of 1931/1932 decimated the seedlings. Those that survived to bloom were hopelessly poor. Bowers’ experience with these really gave the Ironclads a terrible reputation for hybridization. I can remember Paul Vossburg telling anyone who would listen not to use the Ironclads in hybridizing. (Please do not think that Clem’s use of the Ironclads was his only sojourn into rhododendrons; he made hundreds and hundreds of other crosses, finally settling on the use of R. maximum in evergreen hybrids and the selection of super-hardy clones of deciduous azaleas as examples of the genus rhododendron hardy in Binghamton.)

Well, we all know that many hybridizers have been successful with the Ironclads, but usually only when one of the parents in the cross is not an Ironclad. Paul himself made one of the finest hardy crosses on Long Island—’Meadowbrook’. He crossed ‘Pink Everestianum’ with ‘Mrs. C.S. Sargent’ to get ‘Meadowbrook’. Paul told me that out of 135 seedlings of that cross, just three were of any value and ‘Meadowbrook’ was certainly the best of the three. Now Paul was always very insistent that you remember that ‘Pink Everestianum’ was used in the cross, not the common ironclad clone of ‘Everestianum’. Maybe the pink clone has a genetic makeup that is more conducive to creating successful hybrids.

I do think, though, that for Eastern coastal U.S.A. the Ironclads are history. It is fun and really nostalgic to remember back to the ‘good old days,’ but those varieties just don’t compare to what we can grow now.

A list of the Ironclad Cultivars:

Album Elegans

Album Gradiflorum


Caractacus **

Catawbiense Album

Charles Dickens


H. W. Sargent **

Henriette Sargent

Lady Armstrong

Mrs. C. S. Sargent

Purpureum Elegans

Purpureum Grandiflorum

Roseum Elegans

** These two cutlivars were removed, making a total of 12