Here's what you will need:
After cutting your dowels to the desired stem length, hot glue each flower to a dowel, as pictured below.
To additionally stabilize the flower, add a few drops of hot glue between the plastic green base petals and the flower.
Hot glue nip bottles to the center of each flower- make sure they are really centered! For extra stability, add drops of hot glue between layers of petals where needed.
Arrange dowels until your are satisfied with your arrangement. I suggest starting with the middle flower first, and arrange around that.
At this point I still felt like it was missing something. But what? Aha! I placed a call to my hubs, who was still at work: "Could you pick up like, 3 penis pops on the way home?" I know, the call every dude wants to get just before heading home after a long day. Kindly, he obliged and made the stop. They were fresh out of penis pops though (popular item?) so I ended up with these babies: