Two Useful Tips
Here are two tips you should know: The flowers on many cultivars flop over so I straighted a wire coathanger and wrapped it around the plant about 2/3 of the way up the foliage. With the hooked ends adjusted to the right length, the wire holds the plant upright without the use of a stake. The wire is also invisible. In the fall, simply unhook the wire and clean up the foliage.
The second thing you should know is that the only serious disease you’ll likely to see is peony gray mould blight (a form of botrytis) which causes the flower buds to go soft, wilt and turn gray. The solution to this is good air circulation, plenty of sunshine, and good plant hygiene in removing spent flowers and stalks. If it persists, the use of a fungicide such as lime-sulphur will help control it.