Trying to find the correct plant might be difficult, my seed is from the US. I found a photo which is supposed to be from Hart Canna here, I know this company would do it's utmost to name their plants correctly. The photo on the link looks exactly like mine and Sue's, but that one is not on the site and if it is I can't open the link for more photos. I have enlarged the photo on the site using the magnifier and it also has a yellow lip.
http://plantheritage.wordpress...
They are holders of the National Collection of Canna here..
http://www.canna-collection.or...
The photos on Karchesky Canna also match well with mine and Sue's, maybe yours is an Indica hybrid? Canna patens is a small plant.
