Can peonies really change color?
Q. My yellow peony went white right after a late cold snap. What happened? Can peonies change color?
A. Yes and no. The truth is that peony plants don't change in bloom color, but they do seed, and the seedlings often will bloom a different color. As peonies grow and expand, it's easy to confuse the parent plant with some of the new volunteers that come along. Look closely at the base of your plant and you may see that the white flowers are coming from a stem that's separate from the original base plant. Sometimes the seedlings are more vigorous than the parent plant, and may take over the "look" of the peony bed.
If your peonies have been growing undisturbed in the same spot for three years or more, they may have become overcrowded. The best time to divide them is in the fall when the plant is about to go dormant. If the time is right, you'll see new growth buds at the crown of the bush.
Cut back the foliage, and dig out the entire clump. Cut the crown in several pieces, allowing each crownlet to have three to five eyes. Don't cut the thick part of the roots. If you want to hedge your bets, dust the cut surfaces with a fungicide. Plant so that eyes will be facing up, two inches below the soil surface, in moist, well-drained, rich soil in full sun. Water well and mulch.
Although peonies bloom for only a week or two in the spring, you can extend the season by planting early-, mid- and late-blooming varieties.