i think you've missed the boat here, diggity...
ONE flower is hardly akin to a present or gift - it's monetary value is less than $5 if even that and it'll die in two days or so...
it's a thoughtful gesture, plain and simple !!!
any "intelligent" girl/woman is going to know this and considering that, giving someone a flower is not going to be the sole indicator on whether or not the relationship will progress.
geesh, it's a bleeping flower for pete's sake !
bringing flower(s) is not desperate or trying to hard - have you heard of thoughtfulness before ??? believe it or not, some men give flowers bc they are thoughtful & chivalrous.
there is certainly not anything wrong w/that!
as a relatively intelligent and attractive female - i can say wholeheartedly that i appreciate it , bc it tells me that the person was considerate and thoughtful enough to put in a little more effort than simply just showing up at my front door.
personally i find nothing wrong about it at all!!!