dude... do not send them at all... women hate it when someone sends them flowers and stuff at work... trust me on this one, i have heard this from so many of my female friends and co-workers...
just ask her out again and buy her flowers... then tell her that you were thinking of sending them to her work but you weren't sure if she would like that... (this way you get browny points for the thought, without embarassing her in fron of her colleagues...)
send them to her house, or just call her and meet her for five minutes after work (tell her you need to see her for just a second) and give them to her with a "i saw these and thought about you..."
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Dating Advice