Peonies are prized for their sweet smell and rose-like appearance. Unfortunately, peonies are often plagued by insect pests because their sweet odor draws everything to them. If you have peony plants but you cannot stand to deal with the ants, the aphids, the hornets and the rest, here is how you can put the pests down and keep your peonies pretty.
Before the Blooms Burst Forth
In spring, your peonies will begin to grow tall and bushy. As soon as the peonies get their "bloom balls" at the top of the stalks, begin spraying these bloom balls with a pesticide that targets ants, thrips, scale insects and bloom-boring worms. It will deter these pests from attempting to burrow inside before the blooms even shoot forth. Keep spraying the balls about once or twice a week, or after heavy rains, to deter pests from clinging on and waiting the bloom balls to open.
As the Blooms Are Opening
As the peony bloom balls begin to open and the blooms emerge, sprinkle the ground and the flowers with an anti-ant pesticide. Since you do want to attract bees for pollination, you will want to only use a pesticide that kills just the ants. Usually sprinkling the ground around the flower stalks is enough to deter most ants, but if you begin to see ants in the peonies, you will have to dust or spray the blooms as well.
Feed and Water the Peonies a Special Anti-Pest Food
There are also some plant and flower foods out there that you can give your peonies so that they become pest-resistant through their food and nutrient absorption. Some gardeners prefer this to the pesticides because it provides the flowers with nutrition they really need without adding tons of potentially toxic chemicals that can harm humans (the plants and flowers are generally unaffected by pesticides). These plant foods may either be sprinkled on the ground around the peonies or sprayed on via a garden hose and spray bottle application.
After the Peonies Have Finished Their Blooming Season
After the peonies have finished their blooming season, cut the stalks back close to the ground and toss them away. Any pests that may try to lay eggs or overwinter in the old stalks will be gone and cannot emerge and pester your new peonies next spring. The peonies will grow fresh new stalks and it will be easier to take care of them then.