Here are some views of the outfit (front and back) without the foliage. The ribbons that you see tacked onto the bodice are the way that the foliage will be kept on.
And here is how the costume looks (front and back) with the foliage attached. I managed to find ivy leaves in a pre-made vine. The "stem" of the vine was formed with little loops for easy hanging, which became quite convenient for my cause.
A detail shot of how I tied down the foliage to the costume.