Black Stem Elephant Ear, Black Taro, Etc.
Colocasia fontanesii Schott is the correct and accepted scientific name for the Black Stem Elephant Ear. It was named and described by Heinrich Wilhelm Schott in Oesterreichisches Botanisches Wochenblatt 1854.
The genus, Colocasia Schott, was also named and described by Mr. Schott in Meletemata Botanica in 1832. Plants of the World Online by Kew currently lists 10 accepted species in the genus Colocasia (when this page was updated on October 10, 2018).
Over the years the Black Stem Elephant Ear has been listed as several different species which was a bit confusing. The last update of The Plant List (no longer maintained) said it was Colocasia antiquorum. Although Colocasia fontanesii was listed as a synonym of Colocasia antiquorum on The Plant List, NOW Colocasia fontanesii is once again the correct name. Colocasia antiquorum IS NOW considered a synonym of Colocasia esculenta… At least that’s what Plants of the World Online by Kew say.
I bought my Colocasia fontanesii ‘Black Stem’ from Brent & Becky’s in the spring of 2012. I also bought an Alocasia ‘Black Stem’ from Wellspring Gardens. I thought maybe they were the same plant, but sure enough, they were different. The Colocasia leaves pointed downward and the Alocasia pointed upward. Very strange that there is a species of Alocasia and Colocasia that look so much alike except for the direction the leaves point…
Black Stem is not a cultivar although many sources list them as ‘Black Stem’. Black Stem is the common name.
Colocasia fontanesii is the correct species name (for now AGAIN), but it is listed online as Colocasia antiquorum, Colocasia antiquorum var. fontanesii, Colocasia esculenta var. fontanesii… Sure I missed at least one.
Origin: Assam, Bangladesh, South-Central China, East Himalaya, Laos, Myanmar, Thailand
Zones: USDA Zones 7b-11 (5 to 40° F)
Size: Up to 6-8’
Light: Prefers light shade
Soil: Prefers moist soil
Water: Yes. 🙂
I am no aroid expert and I only grew this plant as a companion for one season. I liked its dark stems and dark green leaves and had no problems with it at all. As with many Colocasia, if you buy as small plants grown from tissue culture, it can take some time for them to reach a dramatic size. So, if you buy smaller plants and they don’t get 6-8’ tall by the end of the summer, just be patient. They now have rhizomes that you can store for the winter and they will make larger plants the next season. Unless you live in a zone they can stay out all winter… Just make sure the rhizomes don’t remain too wet over a cool winter outdoors.
You also need to make sure you have your Colocasia growing in an area they like and will do well. Otherwise, your plants will not grow well and attain any size. When I lived in Mississippi, the Colocasia esculenta grew HUGE. Now, in mid-Missouri, I only have room for two that can grow HUGE and the rest remain small because of where I have to grow them.
Keep in mind that Colocasia grow a new rhizome every year on top of the old one. If they are not in a location where they will thrive, the new rhizome could be smaller than the old one.
Someday I will purchase another Colocasia fontanesii since I left the first one behind in Mississippi.
I hope you enjoyed this page and maybe found it useful. If you have any comments, questions or suggestions, I would like to hear from you. Please click on “like” if you visited this page. It helps us bloggers stay motivated. 🙂 You can check out the links below for further reading. The links take you directly to the genus and species of this plant. If you notice I made an error, please let me know.
There isn’t any WOW information online right now about Colocasia fontanesii. Most of what is there is out of date and I try and be as current as possible (even though it has been six years since I grew this plant…). I will update the blog pages off and on to make sure the scientific name is still current and maybe there will be new and better information available.
*Dave’s Garden still says the accepted species name is Colocasia antiquorum. They either aren’t up-to-date or decided to leave it that way.
*The Wikipedia is also not up to date yet…