Karen Scholle answered:
I don't know what type of paint was used on the side. I would think a Rustoleum type paint was used. It was already painted when passed down to me. The daylilies love it and are about 4 feet tall now! I put in various annuals every year to change it around. In front, I have tube roses at the back and Iris all in front. On either side I chose Peonies to put there. HINT: make sure you put it on a slab of stone or heavy wood, it will sink when all the dirt and flowers are added, along with the time it sits there. I have really enjoyed having it in my yard! it is a fun piece!