JARS v39n1 - Rhododendron Adventure in North Germany

Rhododendron Adventure in North Germany
Carl S. Hoveland
Professor of Agronomy, Athens, Georgia

North Germany is not on the itinerary of most tourists but for an American rhodoholic it is a beautiful and exciting area. Although this region is relatively unknown to most American rhododendron lovers, several German garden books indicated that north Germany offered not only beautiful gardens and nurseries but also the opportunity to meet outstanding rhododendron breeders and view the fruits of their work.
Having made plans to attend a scientific meeting in Norway during June 1984, I contacted several German members of the American Rhododendron Society for information on rhododendron gardens that I might visit in north Germany. In response, Dr. Klaus Luck, M.D., of Kiel sent a detailed travel itinerary and Richard Reuter, instructor at the nursery school in Elsmhorn, made contacts and set up a schedule of visits. Leaving Atlanta on June 5, I flew directly to Amsterdam where I traveled by train to Bad Zwischenahn in the moors and marshes of Lower Saxony near the North Sea. Here I was met by Johann Wieting who operates a nursery at Westerstede. Huge rhododendron plants in full bloom across the street from the railway station welcomed me. Although light rain was falling, the ride to Westerstede was beautiful, as we passed fields of rhododendron and azaleas in bloom. This, as I was to learn, is the heart of the rhododendron nursery industry in Germany with about 620 acres of rhododendron. A tour of Wieting's beautiful large garden at 7 p.m. revived me even though my internal clock said it was midnight. A leisurely dinner and conversation with Herr and Frau Wieting and their daughter Hide was a for taste of the marvelous hospitality I was to enjoy in north Germany.
The next morning Wieting and I visited the nearby Bruns nursery or baumschle (literally, plant school) which consists of a 160 acre rhododendron and azalea garden and a large nursery. Wandering along trails with well-labeled rhododendron and azaleas in bloom was sheer delight. Wieting's knowledge of cultivars and their adaptation was encyclopedic. Familiar cultivars from England and the USA, along with older German hybrids, were everywhere. Most interesting to a visitor were new hybrids from the Bruns breeding program. 'Seestadt Bremerhaven' ( R. insigne x 'Prof. H. deVries') with tight trusses of white flowers edged with bright rose, was spectacular. 'Cleopatra' ('El Alamein' x R. insigne ) with deep rose flowers, 'Bad Zwischenahn' ( R. yakushimanum x 'Doncaster'), a brilliant mass of pink blooms, and 'Gloria' ('Goldsworth Orange' x 'Prof. Bettex'), white edged flowers with apricot-colored throats, were especially lovely.
A tour of Wieting's 15 acre nursery was impressive. Although his nursery is not large, he produces over 350 rhododendron cultivars, the largest number in the country. Most are propagated by grafting, mainly on 'Cunningham's White' root stock. In contrast to propagation of rooted cuttings in the USA and England, German nurserymen produce 80% of all hybrids on grafted stock which they claim are more vigorous, more tolerant of alkaline soil and drying, and result in more compact plants. Cutting production is usual for 'Catawbiense Boursault', 'Roseum Elegans', 'Cunningham's White', R. repens hybrids, and R. williamsianum hybrids. The high quality of plants attest to the skills of German nurserymen like Wieting.
In the afternoon, Berthold Leendertz, a landscaper and retail nurseryman from Krefeld near Cologne, joined us for a tour of Dietrich Hobbie's 160 acre rhododendron garden and nursery in an old pine forest at Linswege near Westerstede. Dietrich Hobbie, now 85 years old, and his daughter Elisabeth welcomed us. Rain showers made for a wet walk so we rode around the garden in Herr Hobbies Mercedes car as he discussed his breeding career and pointed out plants of particular interest. Species from China, Burma, India, Europe, and North America are found in his huge collection. Unfortunately, many of these rhododendron species and hybrids are unlabeled and the only other person besides Hobbie who knows the plants is Wieting. Hobbie is an intense man who lives and thinks rhododendron all the time, this having been his entire life's work. He offered an opinion on American rhododendron breeding that we do not test hybrids long enough before release. He claims it takes 20 years from the first cross until it is ready for release. Rhododendron breeders must start their life's work when they are young and live to old age!

Dietrich and Elisabeth Hobbie in their
rhododendron garden at Linswege.
Dietrich and Elisabeth Hobbie in their
rhododendron garden at Linswege.
Photo by Carl S. Hoveland

The Hobbie garden, on soil with a pH of 4 to 5, contains huge old plants of common older cultivars like 'Gomer Waterer' along with a large number of Hobbie releases such as the red R. repens hybrids 'Baden-Baden', 'Elisabeth Hobbie', 'Scarlet Wonder', R. williamsianum hybrids such as the rose colored 'Gartendirektor Glocker' and 'Stadt Essen', R. wardii hybrids such as 'Nippon', the yellow R. yakushimanum hybrid 'Flava', and the spectacular large-trussed pale pink R. discolor hybrid 'Wilhelm Schacht'.
Another day was spent with Berthold Leendertz touring the government Horticulture Research Station near Rostrup which contains the largest collection of rhododendron and azalea cultivars in Germany. Walter Schmalscheidt, in charge of the 7.5 acre rhododendron and azalea test garden, has authored a book on the history of Germany rhododendron breeding and is working on another book. He toured with us awhile, then returned to his evaluation work. Three plants of each cultivar are grown, all well-labeled. Superb dwarf conifers add to the beauty of the garden which is open to the public.
Although the peak bloom in this open unshaded garden had passed, there was still plenty of excellent color to excite the eye. Leendertz was a splendid person to tour with as he had travelled extensively in England, China, USA, and New Zealand to visit rhododendron in gardens and in natural habitats. As we talked and photographed flowers, we had an exciting time. This garden contains many old English hybrids not common in the USA. The old German Seidel hybrids are well represented. Very few Dexter and Shammarello hybrids are present although they are very well adapted in this region where cold hardiness is a problem. One of Leendertz' favorites was a lovely pink Waterer hybrid, 'Sneezy'. Rhododendron species are well represented in this collection.
One afternoon we toured the past harvesting area at Leer near the Dutch border in East Friesland. One large rhododendron and heath nursery is located on peat land with a pH of 3.5 to 4.5 so lime is added for satisfactory plant growth. It was remarkable to see rhododendron thriving so well on this poorly drained peat land.
After the great hospitality of the Wieting's, Richard Reuter  from Elmshorn escorted me on the remainder of my north German tour. At Bremen is the 40-acre Rhododendron Park developed by the German Rhododendron Society. It contains magnificent plants of older cultivars and a good collection of newer hybrids. Plants of species such as R. sutchuenense var. geraldii from Hupeh, China were thriving outside. Plants of less cold hardy species such as R. hemsleyanum from Sichuan, China were blooming in the glasshouse.
Based at Elmshorn, we made tours to Hamburg and visits to rhododendron, heath, and conifer nurseries in the Pinneberg and Barmstedt area. Rhododendron production in this area is low, totaling only about 75 acres. The new Hamburg Botanical Garden is lovely, being divided into areas representing habitats in different areas of the world. They had gone to great effort in representing flora of different regions. In the area representing the southeastern USA, Spanish moss ( Tilandsia ) was kept in a glasshouse during winter and then hung on trees outside during the spring and summer. Unfortunately, rhododendron were only a minor part of this botanical garden. R. calophytum from western China was thriving here.
A pleasant surprise was the Ohldsorf Cemetery in Hamburg which has huge old rhododendron, mainly 'Catawbiense Boursault', which are 50 to 100 years old. The rhododendron, in full bloom, were lovely as they nearly obscured the grave stones under the shade of huge old conifer and deciduous trees. It seemed more like a park than a cemetery and people used it for walking and bicycling. Another city cemetery at Pinneberg, was smaller, 50 acres, but even more beautiful with a profusion of many rhododendron cultivars in bloom under the trees. It is one of the most beautiful cemeteries I've ever seen, all maintained with typical German gardening skills by city employees.
Richard had saved the best visit until last, an afternoon with Hans Hachmann and his 32-acre nursery at Barmstedt. It was a bright sunny day and the gardens around his home and nursery headquarters blazed with rhododendron and azaleas in bloom. His son, Holger, who speaks English, welcomed us and then introduced his father who was at work pollinating rhododendron flowers. Hans Hachmann, a gentle smiling man who speaks no English, seemed pleased to have an American visitor intrude on his busy schedule. Fortunately, it was a Whitsun Holiday that Monday and the nursery was closed.

Hans Hachmann, his wife, and son Holger
in front of his hybrid 'Feuerschein'.
Hans Hachmann, his wife, and son Holger
in front of his hybrid 'Feuerschein'.
Photo by Carl S. Hoveland

What is so remarkable about Hans Hachmann? Touring the garden and viewing his creations, a rhodoholic can become ecstatic. His most spectacular hybrid, 'Hachmann's Feuerschein' (Fireshine), is a hardy scarlet red elepidote ('Nova Zembla' x 'Mars'). It has large-flowered scarlet trusses with white-tipped anthers, rich dark green leaves, and is hardy to -17F. A lovely sister seedling, 'Blinklicht' (Blinklight), is lighter red and less cold hardy (-5F). 'Sammetglut' (Velvet Glow), a 'Mars' x 'Nova Zembla' cross, has scarlet flowers with white anthers, compact dense foliage, and cold hardiness to -17F. Some remarkable red R. yakushimanum hybrids include 'Morgenrot' (Morning Red), 'Polaris', and 'Fantastica'. Yellow hybrids include 'Goldkrone' (Gold Crown), 'Graf Lennart' (Count Lennart), and 'Festival'. Other hybrids include the cream color 'Bernstein' and 'Maharani', lilac color 'Holstein', pink 'Diadem', purple 'Kolomba', late-blooming red and pink 'Juniperle' and 'Meteorit' (Meteorite) with a large red blotch on white petals. Among his many new azalea hybrids is the brilliant fire-red 'Feuerwerk' (Fireworks).
In all, Hachmann has developed over 60 new hybrids, many of which have won top medals in European shows. Over coffee and cake with his family, we discussed his breeding work. Since 1952 he has made 150 crosses annually, grown 20,000 seedlings per year from which he selected 14 to 30 seedlings for further testing. This colossal breeding program has been entirely financed by his wholesale and retail nursery operation, utilizing a staff of up to 17 gardeners. His objectives in breeding are (a) low, compact growth, (b) pure bright flower color, (c) good leaf growth and cold hardiness, (d) large-flowered dwarf plants, and (e) lime tolerance. His determination, dedication to excellence, and genius have resulted in his being acclaimed the greatest rhododendron breeder in Germany today.
What is the potential for Hachmann's hybrids in the USA? The harsh north German climate has resulted in hardy plants that should thrive in the eastern USA where many West Coast hybrids fail. Since Dexter, Shammarello and hardy English hybrids do well in north Germany, one would expect many of Hachmann's hybrids to thrive in the severe climate of the eastern USA.
Hachmann cautioned that his hybrids might not look as good in the USA if they are grown as rooted cuttings. He illustrated this in his garden by pointing out the compact growth of a 'Feuerschein' plant grafted on 'Cunningham White' rootstock adjacent to a plant of the same hybrid with less attractive open foliage and more widely spaced trusses when grown from a rooted cutting. The breeder from Barmstedt modestly added, "there are no shortcuts in rhododendron plant production, just as in breeding."

Dense compact growth of 'Feuerschein'
grafted on 'Cunningham White' rootstock.
Dense compact growth of 'Feuerschein'
grafted on 'Cunningham White' rootstock.
Photo by Carl S. Hoveland

After visiting Hachmann, my host Richard Reuter informed me that I had met the most knowledgeable rhododendron people in Germany - Hachmann, Hobbie, Leendertz, Schmalscheidt, and Wieting. As an amateur rhododendron grower, I was overwhelmed and impressed with the vigor, creativity, and output of the north German rhododendron industry. Their hospitality was genuine and kind, just as it is among rhododendron gardeners in the USA. My final visit as a guest in the home of Dr. and Mrs. Klaus Luck at Kiel confirmed that point. I had visited many of the gardens in his detailed itinerary but he pointed out that I had not visited a number of other rhododendron gardens at Dortmund, Essen, Dsseldorf, Cologne, and Krefeld. I must return again, and I must come 2 to 3 weeks earlier when his own large garden would be in bloom. North Germany may not be for the average tourist but it is a grand place for a rhodoholic!