What happened to my peony planted last year, and does a tree peony need pruning?

As your tree peony was planted last year and already produced two flowers in early July, this looks more like a young plant establishing than something going wrong. Tree peonies often start slowly, and flowering can be sparse during the first few years before the shrub gets going.

Prune very cautiously

A tree peony should not normally be pruned hard. Let its branch framework develop. In spring, once you can see which parts are alive, remove dead, blackened, broken or clearly dried shoots, cutting back to healthy wood or a living bud. You can remove spent flowers after flowering, but cut off only the flower remains rather than cutting down the plant.

The leaf spots

You also ask about the leaf spots. On tree peonies, these are often leaf-spot problems encouraged by moisture, dense foliage and older leaves later in the season. Weather changes can also leave marks. If the leaves are spotted but the plant otherwise grows and flowers, it is rarely urgent.

• Remove the worst affected leaves if they look unsightly or clearly diseased.
• Clear old diseased leaves from beneath the plant rather than leaving them there.
• Water the soil rather than the leaves where possible.
• Give the plant enough space for its leaves to dry after rain.

Partial shade suits a tree peony, particularly with light for part of the day rather than the hottest sun throughout. For now, the best thing is to let it stay and develop steadily. If spotting increases sharply, leaves yellow early or shoots begin to wilt, investigate fungal disease or drainage problems more closely.