JARS v51n2 - 'Halopeanum': The Story of Its Origin in France

'Halopeanum': The Story of Its Origin in France
Marc Colombel
Fouesnant, France

Let me tell you a curious story showing the importance of a label
In the summer of 1995, the owner of a botanical garden, a Mr. Gueguen near Quimper, Brittany, told me that a Mrs. Madeleine Letribot had visited his garden and saw the label 'Halopeanum' under a rhododendron. She told Mr. Gueguen that she was a granddaughter of Mr. Halop, a French nurseryman. Curiously, in Brittany (west part of France) we did not know it was a French rhododendron. We knew that the English called it 'White Pearl,' but that was all.
We French people, as many others, I suppose, believed what was in Rhododendron Hybrids (Salley and Greer). That is to say: Halope, Belgium, 1896, as its place and date of origin. The same origin was written in Encyclopedia of Rhododendrons (P. Cox and K. Cox). In Hilliers' Manual of Trees and Shrubs in the 'White Pearl' entry there was a note: "see at Gauntlettii." No books about a French connection.
So, I wrote to this granddaughter explaining to her that I needed all the documents to prove the Royal Horticultural Society that Mr. Halop was a Frenchman. I received a lot of documents from Mrs. Le Barbanchon, another granddaughter of Mr. Felix Halop, from Mrs. Mallet Bouchayer and from Mr. Erwan Boudard, who is responsible for the center of documentation of the Sociti Nationale d'Horticulture de France.
We discovered that Mr. Halop was a very well-known nurseryman in the Cherbourg area (Cotentin Peninsula) and that his rhododendron was a chance seedling.

The following documentation was used:
1. Revue Horticole , 1896, pp. 359-360. I think this is the most important clue because on page 360 there is an accurate description - like a registration form. We learn that 'Halopeanum' is a cross between an R. griffithianum and an R. arboreum , Smith (Exotic Botany 1804-1805). ¹ There were several R. arboreum near the R. griffithianum , and Mr. Halop does not know which one was the pollen plant. The seeds were harvested in 1885, and it is only in 1893 that the first flowers appeared. During the winter 1894-1895 there was a terrible frost (for this area). The temperature fell to -16°C, and 'Halopeanum' did not suffer. On May 8, 1896, Mr. Ed. Andre received a flower truss (or trusses) and an aquarelle was immediately done.
2. Revue Horticole . The aquarelle was done on May 8, 1896 (see Figure 1).

3. Revue Horticole , 1896. Mr. Halop reports he has three different R. griffithianum : one pure white and two different pinks. He adds that 'Halopeanum' has to be in full sun to color. The 'Halopeanum' will be sold in 1897.
4. Revue Horticole, 1901 . Awards for the show at the 1900 Universal Exposition in Paris: 'Halopeanum' won.
5.  Account books of Mr. Mallet, 1901 . Mrs. Claire Mallet Bouchayer sent me a photocopy of a part of the book in which Mr. Mallet kept the accounts of his park (vegetables are included). The underlined names are nurserymen, in brackets the town where they worked. Mr. Mallet began his park in 1898 and now the highest 'Halopeanum' is 12 meters high (see Figure 2).

6. Bulletin of the Socit d'Horticulture de Cherbourg , 1912. This is a report about a very interesting visit to Kew. This bulletin says about 'Halopeanum': it is called 'Gauntlettii' here because its introducer in England found his name was better than Mr. Halop's name. So (at the end of page 77 and 78) it tells why there are three names for the same plant: 'White Pearl' for the Dutch introducer, 'Gauntlettii' for the English introducer, and 'Halopeanum' for the obtainer.
7. Encyclopedia of Rhododendrons , P.A. Cox & K.N.E. Cox, 1988. 'Gauntlettii' is generally considered to be synonymous to 'Halopeanum'.

Editor's Note: The first issue of The International Rhododendron Register , published in 1958, lists "(Halope, Belgium, 1896)" as the raiser/introducer of 'Halopeanum' and identifies 'White Pearl' as a synonym. As a result of Mr. Colombel's research, the international registrar Dr. A.C. Leslie has corrected the address of Mr. Halop in the registration records from Belgium to France. The accent has been dropped from the cultivar name. The cultivar name 'Gauntlettii' is being kept as a separate entry for the time being.

¹ According to Notes RBC Edinburgh , Smith is the name of the person who first described R. arboreum .