Cher, I have a pergola (large arbor type) in my backyard perennial garden which DH made 10 years ago. The 4×4 posts are cemented into the ground because of its size and all the wind we have, and it has survived lots of storms other items have not here. Maybe longer stakes will help yours.
Just have to post pic of this garden in 2014, as last year was a horrible year for plants & gardens here. If you zoom in you can see it better. Some of my BB boxes are in this area.
