Saturday, November 7, 2020

Tradescantia spathacea : varieties, cultivars, hybrids

Tradescantia spathacea 'Aureostriata': with golden (yellow) stripes.



In this article you will read my current personal understanding after collecting and studying Commelinaceae plants since 2010. I thought that with my amateur knowledge about botanical latin I can contribute something more into the existing knowledge of this rapidly growing and expanding family of plants: Commelinaceae, which includes plants that many of them grow as weeds and they are plants that easily cross bred with each other without human intervention.
This article is about the Tradescantia spathacea varieties, cultivars and hybrids. There will be more coming soon for other Tradescantia plants and other plants in the Commelinaceae family.


created: Nov. 7, 2020
updated: Aug.. 24, 2021
⚠️Important notes
1a) variety/var. (varietas in Latin): Most Commelinaceae plants are easily crossed to each other and from that crossing new varieties may appear. According to the International botanical nomenclature, a naturally occuring variety is denoted with the denomination var. whilst the taxon name is written with the first letter of the genus capitalized and the rest with small letters. Plus it is written in italics except the var. denomination. Example: Tradescantia zebrina var. flocculosa.

1b) form/f. (forma in Latin): In botanical nomenclature, a form (forma, plural formae) is one of the "secondary" taxonomic ranks, below that of variety, which in turn is below that of species; it is an infraspecific taxon[1]. Variety differs from form/forma in that a variety implies predictable inheritable traits where form/forma traits occur sporadically within a population.

1c) cv./cultivar: a cultivar (or cv. or horticultural variety) is a cultivated variety that originated after human intervention. The names of cultivars are quoted using single quotes '. . .' and the first letter of each name is capitalized. Example: Murdannia ‘Bright Star’. Murdannia ‘Bright Star’ is a horticultural cultivar with unique characteristics that can only be found combined in that specific cultivar. In the past the denomination cv. used to be included in the name ie: Murdannia cv. ‘Bright Star’ but that is currently not accepted. See also the article about the disambiguation of this taxon.

1d) hybrid: hybrid plants are usually sterile and propagated only through cuttings or tissue culture (TC), not by seed. An example of this might be the Tradescantia ‘Bermudensis’ (also known as Tradescantia 'Hawaiian Dwarf') which is a dwarf cultivar originating from the Tradescantia spathacea plant. After many decades since this plant was circulated all over the world there were nowhere flowers to be seen. Only recently have appeared on the internet, three-four images with flowers. Which makes me think that there might exist more than one variegated Tradescantia spathacea plants with white variegation (reminding also the Tradescantia spathacea 'Sitara' which also has white variegation, but it doesn't stay small). Since flowering photos were never released before, it might be the case that the Tradescantia ‘Bermudensis’ is actually a hybrid (remember: a hybrid is sterile, which only can be propagated through cuttings and TC). One plant - in this case Tradescantia spathacea - may have more than one variegated varieties, such as the case with Callisia fragrans ‘Infinity’ and Callisia fragrans ‘Melnikoff’, two seemingly similar cultivars, but they are in fact different.

2) Color changing: Most plants in the Commelinaceae family do change color according to various factors such as: season, temperature, light, location. Thus, two seemingly identical cuttings/plants may come from different cultivars, that have been grown in different conditions and/or kept in different locations (that relates to light levels). An example of this are the T. zebrina ‘Burgundy’ and T. zebrina ‘Deep Purple’. When kept in bright light their colors will be that of each equivalent cultivar (burgundy color for the first and dark purple [almost black] for the second). But when these plants are kept in a location with less bright light their colors tend to look similar and sometimes may even confuse the experts. So keep always that in mind. That is why it’s important to buy from experienced sellers that have both cultivars and have labeled them correctly, in order to avoid confusion.

3) Old names still in use: old synonyms of both genus and species (some of them even from the 19th century) are unfortunately still in use today, bringing more confusion on these matters. These include and are not limited to: pendula, setcreasea, rhoeo.

4) N/A (where applicable) means that I didn’t have a personal experience with the specific plant variety/cultivar/hybrid.

Setcreasea: a genus synonym for Tradescantia, from the 19th century, still in use today.



Tradescantia spathacea - table listing the different names of varieties, cultivars, hybrids

Tradescantia spathacea  This is the regular plant. The regular T. spathacea is a plant that gets big, about 40cm and perhaps even taller, with large sword-like leaves. Sometimes its - very old - synonym Rhoeo discolor is still used today among hobbyists and in the horticultural industry.
Tradescantia spathacea var. nana This is the dwarf variety of the Tradescantia spathacea.
Tradescantia spathacea f. concolor This is a mainly green Tradescantia spathacea with large leaves.
Tradescantia spathacea 'Albovariegata'

Tradescantia spathacea 'Sitara'
It is known as Tradescantia spathacea 'Tricolor', or Tradescantia spathacea 'Sitara', but I don't believe that, that is a cultivar created by humans. I believe is a naturally occuring variety with white variegation, which appeared in the horticultural industry. Etym.: albo (latin for white) + variegata (variegated plant).
Tradescantia spathacea var. nana 'Albovariegata’ It is known as Tradescantia spathacea 'Hawaiian Dwarf', Tradescantia bermudensis 'Variegata' and Tradescantia spathacea 'Sitara'. But there are some mistakes with these names. Firstly, the taxon bermudensis is written in a way as to indicate that it is a botanical species, but there's no such botanical species with that taxon name. Secondly, the T. spathacea 'Sitara' grows larger and there have been circulated 3-4 photos with flowers, therefore I believe there are two white-variegated Tradescantia spathacea varieties. Those that I have mentioned here: One regular size plant that produces flowers and one dwarf sterile (hybrid).
Tradescantia spathacea 'Aureostriata'

This is the yellow (golden) variegated form of the Tradescantia spathacea. It was mistakenly circulated as Tradescantia spathacea 'Vittata' and Rhoeo spathacea variegata 'Vittata' but firstly: The term vittatus is used mainly in zoology, the equivalent in botany is striatus. Secondly: the genus Rhoeo is a very old synonym of the accepted genus Tradescantia. Aureostriata etym.: aureus (latin for golden) + striata (latin for striped [variegation]).

Tradescantia spathacea 'Cream'

This is a new variegated spathacea (Summer of '21) with pastel colors (cream/pink). Her colors resemble those of a different species in the Commelinaceae family, the Tradescantia zebrina 'Danny Lee'.

Tradescantia spathacea var. nana ‘Sitara Gold’

Tradescantia spathacea var. nana ‘Sitake's Gold’
This is the yellow (golden) variegated form of the Tradescantia spathacea var. nana. It's a dwarf (nana) and sterile plant (it does not produce flowers), thus it's a hybrid.
Tradescantia spathacea var. nana ‘Sitara Gold’

Tradescantia spathacea var. nana ‘Sitake's Gold’
This is the yellow (golden) variegated form of the Tradescantia spathacea var. nana. It's a dwarf (nana) and sterile plant (it does not produce flowers), thus it's a hybrid.
This article will be updated whenever more information is available.


Tradescantia spathacea and some other variegated varieties/cultivars/hybrids

1. Tradescantia spathacea 2. Tradescantia spathacea var. nana 'Albovariegata' 3. Tradescantia spathacea var. nana 'Sitara Gold' 4. Tradescantia spathacea 'Aureostriata'.

Tradescantia spathacea f. concolor
a green spathacea with large leaves.


Tradescantia spathacea dried flower bracts with seeds


A historic photo from 1957, showing the true size of the - then known as Rhoeo discolor - Tradescantia spathacea.








References:
1. McNeill, J.; Barrie, F.R.; Buck, W.R.; Demoulin, V.; Greuter, W.; Hawksworth, D.L.; Herendeen, P.S.; Knapp, S.; Marhold, K.; Prado, J.; Prud'homme Van Reine, W.F.; Smith, G.F.; Wiersema, J.H.; Turland, N.J. (2012). International Code of Nomenclature for algae, fungi, and plants (Melbourne Code) adopted by the Eighteenth International Botanical Congress Melbourne, Australia, July 2011. Regnum Vegetabile 154. A.R.G. Gantner Verlag KG. ISBN 978-3-87429-425-6. Chapter I. Article 4


labels: tradescantia spathacea varieties, cultivars, hybrids, mapping tradescantia zebrina

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