Peonies and Ants, A Beautiful Friendship

My peonies are getting ready for their moment in the sun – and I can hardly wait. But before the flowers come, the ants arrive. And they’re here in full force.

Every spring, I get as many questions about ants on peonies as I get ants on my peonies. In other words, lots of them.

But it’s an old wives tale that peonies need ants to bloom. Ants don’t pollinate peonies – and they don’t “unglue” the flower petals like generations of gardeners believed. It’s a charming notion and it’s true that the ants are lapping up the sticky nectar produced by the leaf-like structures that cover the buds. But the blooms would open even if the ants weren’t there.

The thing to remember is that the invading armies of ants don’t hurt the plants. In fact, they actually protect the swelling buds from other less-benign soft-bodied pests. I was talking about all this the other day with David and Kasha Furman when I visited them at Cricket Hill Garden, their lovely tree peony nursery in Thomaston, Connecticut, for an upcoming column. They call their place Peony Heaven so I figured they'd have something to say about the ant-peony phenomenon. And David did. He said the ants feed the nectar to aphids, which are like "domesticated animals." Then, he said, the ants "milk the aphids" and feed the substance to their queen. So whatever you do, please don’t try to wipe out the ants with toxic pesticides.

And be patient – the ants that came marching in will soon go marching out. In the meantime, enjoy your peonies. If you’re cutting bouquets from your garden in the coming weeks, try holding the flower upside down and gently shaking out the ants so you don’t bring them inside. Or submerge the entire cut bloom upside down in a bucket of water for about five minutes to drive out the ants.