What Plants Work Well With Peonies?

What Plants Work Well With Peonies? Peonies enjoy plenty of companion plants, including Alliums, Bearded Irises (Iris germanica), Siberian Irises (Iris siberica), Columbines (Aquilegia), Spring Bulbs, Roses and small shrubs and trees. What can I put around my peonies? Peony cages keep peonies from falling over. Wire tomato cages are perfect for supporting small peonies.