When I am doubtful of the spelling, I often do a search with just the a part of the plant name. In this case, I might enter 'chrys' which would bring up all sorts of plants, but the first couple results were for a specific cultivar of chrysanthemum. I could then open a cultivar entry, and then click on the top bar to go back to a more general search for chrysanthemum. A bit of a handy work-around for me.
