During the times when “gardening from the desk” I often find myself in need of knowing the latin name of a certain plant of which I only remember a name in German or have only heard the Finnish name.
I usually solve this problem quickly using Google search:
My first go is to run a search with the plant name that I have and the search term “wikipedia”. Most likely there is a dedicated Wikipedia page for that plant in the language that I am searching in, and Wikipedia will usually provide a photo and a latin name. The photo is useful to verify that I have found the right plant (assuming I know what it actually looks like).
Sometimes I am actually looking at a family of plants or an entire species, in that case Wikipedia will say so.
If wikipedia is of no help but I know what the plant looks like, I run a Google image search on the name that I have and see whether any site with the correct image has also the latin name (they are often from gardening sites or nurseries, which usually provide the latin names).
I usually then run the latin name in a Google image search to verify that this is the name specific to what I am actually looking for. Too often I then realise that there are many more variations of the plant than I assumed.