JB! Shoe! Good to 'see' everyone. Thanks to JB for hollering in my direction so I poked in over here. God love her but I'm no expert, dog.,,she's just overly gracious with her praise. You'll learn more from JB and Shoe than I could even begin to share! Also remember scent is subjective....what's lemon to one might not be another. Looks like the main 2 were suggested already. Let me share a few more that might or might not have a hint of lemon/citrus to your nose. Winter honeysuckle blooms have a lemon scent to my nose as does Butterfly Ginger to a degree. There re those that believe some of the Daphne blooms lean toward a baby powder/lemon mix fragrance. There is a lemon basil as well as a Thyme if you like the herbs. My NOID Crinum that bloomed last week had a hint of a citrus type scent....although telling you NOID doesn't really help much, now does it (photo below). If I think of any more - I'll pop back in.
Opps notices Shoe's thoughts on the Lemon Basil. He's probably right...you gotta give those leaves a good rub to get that scent where as the 2 he mentioned have a more pronounced lemon scent