Feeding a plant is the same as fertilizing a plant. The two words, feeding and fertilizing, are often used interchangeably by gardeners. There are two species of peonies: the garden or herbaceous peony (paeonia officinalis) and the tree peony (paeonia suffruticosa). The following directions detail how to feed or fertilize the garden peony. Tree peonies have different cultivation requirements and need to be fertilized monthly. Garden peonies are hardy perennials that need little care and only need feeding once a year.
Feed herbaceous peonies in mid-spring or when new growth is 6 to 8 inches high.
Rake mulch away from the crown (where the growth emerges) of the peony.
Apply 1 to 2 inches of compost spreading it around plant. A balanced commercial fertilizer like 10-10-10 can also be used. Apply it according to package directions.
Give the peony 1 to 2 inches of water after applying the fertilizer.
Replace mulch around the peony to hold the fertilizer in place and to keep the soil moist.