Much Ado About Naming

In my article on Thymus citriodorus in Plant Heritage Autumn 2005 I referred to a golden variegated, lemon-scented bushy thyme supposedly collected in northern Spain and given the name T. citriodorus 'Villa Nova'.  Joe Sharman obtained this thyme for me from a well known German nursery in late 1997.  He was informed that this thyme had been collected in Spain by friends of another German nurseryman, who had named it after the village where it was found, Vila Nova, but he later realised he had spelled it incorrectly.  The thyme grew very well and I first listed it in the RHS Plant Finder in 1999 and it was also one of the thymes we used in the golden thyme DNA study in 1999.

At that time I thought it was rather curious that two of the variegated golden thymes, T. citriodorus 'Golden King' and T. citriodorus 'Villa Nova', had similar profiles.  Although I have a very methodical way of labelling samples and rely on Dr. Madan Thangavelu's expertise, I assumed that somehow despite all our endeavours, somewhere along the line the samples had been mixed up.  As these variegated thymes were used as controls and another had failed to give a profile, I did not pursue the matter, intending to repeat the study at a later date with a larger sample of thymes.

Shortly before Christmas 2005 I was contacted by my Dutch nurseryman friend, Roger Bastin, who told me that he had spoken to the German nurseryman who named T. cit. 'Villa Nova', but who now gave a different version of its provenance.  Apparently someone had found an unlabelled plant at a garden centre near Barcelona and had given it to him.  As he liked the plant and wanted to propagate it, but could not sell it without a name, he named it 'Villa Nova'.  (The actual village is in the north west of Spain!) Neither Joe Sharman nor I had any reason to doubt the name, considering its source.  There is now no doubt that this plant is the very garden worthy T. cit. 'Golden King' as demonstrated by the DNA profiles.

Sadly this is typical of some nurserymen who for one reason or another feel the need to rename a plant.  Some do not take the trouble to find out the correct name when they discover a good looking plant which has lost its label and innocently rename it causing problems for gardeners who may end up with the same plant under two different names.  Others may decide that the original name is not catchy enough for marketing purposes and feel they can sell more plants with a more sophisticated name.  The worst offenders are those who rename a plant to honour either themselves or their nursery, with the intention of passing it off as a new plant.

There are numerous examples, one of the better known of which is the renaming, by a well known seed company, of Geranium pratense 'Striatum' to G. pratense 'Splish-splash'.  It may look good on a plant label but it is incorrect.  The very pretty silver variegated creeping thyme, Thymus 'Hartington Silver' was found by the owner of Highland Liliums growing in a garden in Sutherland.  The owner of the garden claimed she had no idea where it came from, so he named it T. 'Highland Cream' after his own nursery.  In fact the original plant came from Frank and Marjorie Lawley's beautiful garden, Herterton House Garden, at Hartington in Northumberland and they named it.  Players from Sutherland used to visit the nursery when they went to the Durham festival and took the plant home with them.  A National Plant Collection Holder Judy Barker has several old cultivars of spray Chrysanthemum which have been found without labels in old gardens and which have subsequently been given names relating either to the garden of origin or the nursery selling them.  For example a Mr. and Mrs. Perry who run a nursery, found a Chrysanthemum in an old garden and named it C. 'Perry's Peach'.  This has caused confusion with Amos Perry the Enfield nurseryman and Chrysanthemum breeder, who had no connection whatsoever to them.  A couple of years ago Keith Hayward who holds the NPC^® of Canna finally sorted out a major problem with C. 'Durban', now known as C. 'Phasion'.  A South African nurseryman was selling what he claimed to be a different plant, under the name Tropicana, with Plant Breeders' Rights; a potentially profitable exercise.  The Collection Holder took the case to the EU Plant Variety Office, was able to demonstrate that the two cultivars were in fact the same plant and the PBR was rescinded.

As National Plant Collection^® holders we must always question any information we are given regarding names of plants, despite their source.  It is essential to check the literature, particularly old nursery catalogues and compare like named plants from various sources, with the aim of being able to recognise each cultivar.  We observe the plants within our Collections throughout the year and learn to recognise each one's changing characteristics as the seasons progress.  As in the case of the Canna we need to monitor names and verify them wherever possible and if need be, challenge any incorrect names.  Personally I check all the Thymus names in the RHS Plant Finder each year and for nearly ten years, in consultation with the RHS Advisory Panel on Nomenclature and Taxonomy, I have been engaged in sorting out the muddle of Thymus nomenclature, renaming plants where necessary and this is an ongoing task.  Whenever I encounter a nomenclatural problem I adhere to the practice of the RHS, retaining the old name until I have sufficient corroborative evidence to justify a change of name.  This was the case with the golden leaved, lemon scented thymes which we able to place correctly in T. pulegioides and T. vulgaris 'Golden Pins', T. v. 'Dorcas White' and T. v. 'Snow White' which had been wrongly placed in T. richardii subsp. nitidus. (see my article in Plant Heritage Vol. 9 No.1, Spring 2002)

One of my problems is that so many cultivars of thyme have been named by nurserymen and much of the time there is very little difference between them so that it is practically impossible to tell some of them apart.  The golden variegated thymes T. ccitriodorus 'Golden King' and T. citriodorus 'Golden Queen' are so alike that the only way to differentiate between them is that the latter reverts to green and the former does not.  Thymus serpyllum 'Pink Chintz' is very distinctive and unlike any other cultivar, as are T. 'Doone Valley', T. 'Hartington Silver', T. 'Pink Ripple', T. s. Goldstream' and T. s. 'Rainbow Falls'.  Maybe nurserymen should be more discerning in choosing which new plants to introduce to the trade and which should be consigned to the compost heap!

This article was first published in Plant Heritage Vol. 13 No. 1, Spring 2006