Sometimes people aren't home. Okay, a lot of times people aren't home. In that case, I just leave the rose on the doorstep with a note explaining who it's from and any message the person wanted me to deliver. Hopefully it will be a fun "welcome home" surprise for them.
Recently I got a call from my neighbor friend who cleans houses. She had received a rose a couple years back when I used to play the game in my own neighborhood, so she knew all about it. Well, she was calling to tell me she had just been to a client's house (a few miles away) and found a rose that I had left on that doorstep that day! Small world, eh?