As sweet as your smile, my dahlia

 dahlia
In the language of the flowers, depending on which source you use, the dahlia means gratitude, dignity, pomp, instability and misrepresentation
 dahlia
 Geraldine Adamich Laufer provides these even more specific meanings
 dahlia
 double dahlia—participation 
single dahlia—good taste 
 dahlia
 variegated dahlia—I think of you constantly 
white dahlia—gratitude to parents
yellow dahlia—I am happy you love me
 dahlia