Experts and BHG readers answer.
Peony leaves black
Well, peonies should be transplanted in fall, not in spring when they are about to bloom, but there is nothing to do about that now. Let's deal with the present problems. First off, they might not bloom for years--peonies sulk after transplanting becaus they don't like root disturbance. Make sure they are getting full sun and that the soil around them has good drainage. If water takes a while to drain off, add compost to the soil around the plant but be careful not to disturb the roots. Are the peonies planted at or near ground level? If they are planted too deeply, they won't bud. As to the blackened leaves, peonies need a lot of air circulation to thrive. Water them just at the roots so water doesn't get on the leaves. Make sure they have plenty of light and air by trimming back shrubs and trees around them. Remove the black leaves now and discard them.