Why Peonies Do Not Bloom

Mary Lou Hammock, KC Master Gardener 1996

The question of why peonies do not bloom is an important one to resolve for those gardeners who have planted and nurtured peonies with the anticipation of the delightful blossoms that were expected to come. The following list may provide some insight or tips to consider when assessing the lack of blooms:

·     The plants may be too young and immature for blooms and must be allowed time to develop.

·     The plants are planted with the eyes more than three inches under ground.  If so, raise the eyes to the proper depth of two inches under the ground.           

·     The plants have been planted in large clumps without proper division. Dig them up and divide into small or standard divisions and replant them. This problem is a common cause of bloom failure.

·     The buds may have been killed by a late frost.

·     The buds may have been killed by disease.  Spray them with the indicated solution.

·     The buds may have been attacked by thrips.  This is indicated when the buds open partially, turn brown and then fall off.   Spray them with the appropriate solution.

·     The buds may have become waterlogged, again turning brown and refusing to open. Bagging the plant would help.

·     Plants that are undernourished may show buds that never develop. Fertilize the plant to increase its strength.

·     The ground may be too dry.  Watering down to the roots is beneficial.

·     Nematodes or root knot, or perhaps both, may have infected the roots of the plant. Destroy the plant.

·     Moles may have undermined the plants.

·     Weather that is excessively hot is often the cause of the failure of full doubles.  There is no remedy.

·     There is competition for light and other resources when planted too near trees, shrubs, or crowded by other plants.  Consider a different location.

·     When the plants experience too much shade they become tall and leafy.  Plants must be moved.

·     Plants may be being moved and divided too often. Peonies should be planted and left alone, moving them only when absolutely necessary.

·     The plants may be over fertilized with nitrogen rich fertilizers.  Cut down on the amount used.