Peonies and Ants

Ants and peonies go together like peanut butter and jelly. The association is so strong that much folklore has developed around the issue of ants on peonies. Some people even avoid peony gardens because they fear brushing past plants and having ants scramble onto them. Peonies and ants do have a relationship, but it’s rooted in science, not folk tales. The bottom line is that if you grow peonies, ants will come.

Many gardeners worry that when they see ants on peonies they need to break out pesticides to shoo ants away. Nothing could be further from the truth. Peonies and ants forge a partnership of sorts. Do peonies need ants to bloom? The folklore from peony gardens states that they do. This isn’t true. Peony blossoms open whether or not ants are scrambling all over the flower buds.

When you look at a peony flower bud that’s starting to open, you can see green scales covering and protecting the forming blossom. These green scales have a specialized plant gland known as a nectary along the outside edges. Nectaries produce nectar, which is basically a blend of sugar, water and amino acids. It’s an ideal food source for foraging ants.

As ant scouts are wandering around your peony garden, they’ll discover the opening peony buds that are oozing nectar. That scout ant creates a pheromone trail that shows its fellow worker ants the way to the peony buffet. After that, you’ll see ants on peonies until the flower show is done.

To a certain extent, ants actually take advantage of the peony flowers, harvesting much nectar from the plants. But the peonies also benefit, in that ants often devour any insects that are attacking the plants. Gardeners who tend roof gardens have reported growing peonies without any ants showing up. But for peony gardens at ground level, having ants on peonies is a reality.

Typically the presence of ants in the peony garden is a temporary affair. They come for the flower opening and disappear as blooms start fading. There’s no need to spray a pesticide to drive away or kill ants on peonies. They’ll eventually exit the peony plant and move on to fresh food sources.

If you want to cut peony blossoms for bouquets and don’t want to carry ants indoors, take a page from the books of professional flower growers. They usually follow one of two practices to separate peonies and ants. The first method is the surest: Cut peony flowers before buds fully open. At this stage, it’s a simple thing to brush ants off buds.

To use this method successfully, you have to cut the peony flowers at the right stage so the buds will keep opening indoors. The best stage is what’s known as the marshmallow stage. At this point, the bud should be opening and showing some petal color, and the bud should feel like a marshmallow if you give it the gentlest of squeezes.

To ditch peony ants from flowers that are open, hold blooms upside down and given them a gentle shake or two. Hold the stem just below the flower head to avoid having the bloom snap off. Watch for ants scrambling after you shake the blossom. Flick away any that are still clinging to petals.