Peonies come in early, mid, and late season plants. To extend the season even more tree peonies are classified the same way.

The length of the bloom depends on your weather, mostly temperature. I have waited weeks for a bud to open only to come home after work and find the petals on the ground. Since weather is not something we can control consider studying the various types and planting different ones for a succession of blooms. Be aware that the darker the color of bloom the quicker the bloom will be over because the dark colors absorb the heat. My favorites are the darker reds which I plant in more shade than the rest.

Good luck on finding several that you can fit in your garden.

It came to me just before I fell asleep that probably the reason that you thought peonies bloomed forever was that you had some of the old garden/cabbage roses blooming in the same area as the peonies.

You might want to look at some of the pictures on this site to see if they are what you are remembering. Sorry to lead you down another garden path.

Here is a link that might be useful: Old roses

If I understand your question correctly, no, there is no way to get peonies that bloom longer. Whether they are early season, mid season, or late season peonies, they will all bloom for a couple weeks tops, and that's it for the year.

But oh, those blooms when they do bloom! Guess that is the reason we keep on planting them even though they don't bloom for most of the year.

Kate