It looks like the petal tip used flat against the cake for one row, then pulled out slightly and ruffled for the next, then they went over the seem with a small round tip in a loose pattern. Then the top is just the petal tip ruffled.
That is my guess anyway. Beautiful cake!
It might be the 402 or 403 tip
but I think you could do it with a rose tip as well.
This is not the 403 or 403 tip.
This is any of 124, 125, 126, 127 which have straight sides and are the right size for the sides of cakes. You can try 104 in a pinch if you have it.
Thanks so much for the replies! Now to grab the tips and get practicing!
I tried this technique last night. I used the 104 and it looks very similar to what is pictured. I was practicing on a glass and becuase of the angle i was holding the glass i think the ruffles came out better than on the cake. Still very cute though. I am making a baby shower cake and the theme is shabby chic. I plan on putting a large fondant flower on top. I can take a picture tonight and send to you.