While ants are commonly found on peonies they are not required for them to bloom.
Wondering what to do about those ants crawling all over your peony buds and flowers? The answer is simple: do nothing! The ants are not harmful—in fact, according to multiple sources, they’re beneficial. Ants are attracted to the buds because they secrete a sweet, sugary substance that provides nectar for them. Once the nectar is gone, the ants disappear, no harm done.
How are they beneficial? They protect the buds from aphids, thrips, and other harmful predators that would suck juices from the buds and from the rest of the plant. How? If you’ve ever seen films of ants fighting one another, you know they can be fierce competitors. So ants protect their territory by stinging, biting, or spraying invaders with acid. So leave them alone! No need for insecticide.
Two other ideas should be laid to rest—the myth that peonies need ants to “tickle” the buds open by crawling over them. Not true. With or without the ants, peonies will open into the gorgeous flowers we all love. Nor do the ants eat the buds. They simply want the nectar.
Of course, when you bring bouquets into the house you might want to ensure there are no ants in the blossoms. To do this, one source suggests inverting each cut blossom in a shallow bowl of cold water. The ants should float out. Gently shake the blossom to see that no others remain then pour water and ant onto the soil.
In all, let the ants do their thing; they do no harm and, in fact, quite a bit of good.
Then, why aren’t my peonies blooming?
There are, however, other real reasons why your peonies may not be blooming. One reason may be because they are planted in too much shade. Another possibility is that the eyes are planted too deep. There may be other causes too; those tend to be the most common.
There are 4 main types of peonies.
There are 4 main types of peonies: Standard, ITOH, tree peony and the fern peony. Peonies bloom in late May to early June and make a sensational cut flower for their beauty and fragrance. Just be sure to shake them before bringing them into the house in order to remove ants and insects.
Standard peonies are herbaceous peonies. Fern peonies are also herbaceous while tree peonies have woody stems. Intersectional Hybrids are a cross between herbaceous and tree peonies.
Tree peonies have woody stems so they do not die back in the fall after the first frost. They may require winter protection, especially in northern Iowa. They can be grown in hardiness zones 4-8.
ITOH peonies are named for the hybridizer, Toichi Itoh, who first successfully crossbred a tree peony with a herbaceous peony. These have huge beautiful blooms and tend to look like tree peonies.
Fern peonies are easy to identify by their fern like feathery leaves and impressive crimson bloom. They are sometimes called Mother’s Day Peonies because they bloom a few weeks earlier than other peonies.
Care of peonies.
After Peonies finish blooming in the spring deadhead (removing the flowers that are spent) them but keep the leaves. They will produce and store food for the next season resulting in more blooms next year. Large peonies can be divided and transplanted in September and their foliage can be cut back after they die back from the first frost, in late October or November. The most common diseases to watch for are Botrytis blight, Leaf blotch and Powdery mildew. These fungal diseases are visible on the leaves. Powdery mildew is a fungal disease that appears as light gray or whitish powder on the leaves. Copper fungicide can be used but powdery mildew rarely damages the plant permanently.
Learn More About Growing Garden Peonies from Iowa State Extension.