in the course of my browsing i find all kinds of unreliable (no names or incorrect names) images. might be great to look at, but not exactly a reference.
so today i found this flickr collection from german gottingen bot-garden. since bot gardens usually have labels, at least then you can be assured of accuracy of names.
https://www.flickr.com/photos/...
i'll try to add some other sites as i find them. i've seen some in latam bot-gardens too.
hope, other people can post their findings here too
it would be great to have a ready pic-ref and also nice just to flip thru it in free time!