Protecting open peony blooms from a hard rain event can be tricky. Rain can physically damage petals and make heavy blooms flop. Ther is not a perfect “cover” that will prevent damage without creating other issues like crushing blooms or trapping humidity. The most reliable approach is support plus an optional temporary rain roof.

Peonies commonly need support because of their heavy blooms. Staking or support is most effective when it is in place before plants flop. This will not keep the petals dry, but it will greatly reduce the stem breakage that heavy rain events can cause.

If you want to try a cover, use a rain “roof” not a wrap.

If you try to cover them during the rain event, aim for a small, overhead canopy that does not touch the flowers or the foliage. You can create a “roof” by using 3-4 stakes around the plant and attach a board or rigid piece of material frame and then drape plastic over the top like a roof with a slope so the water can run off. Keep the sides open for airflow and remove it as soon as the storm passes to avoid prolonged wet, stagnating conditions. Wet, humid conditions and wet foliage can increase fungal disease problems, so airflow and quick removal are key.

There is also an option to cut the flowers before the storm and enjoy them indoors.

Below are some links for more information about growing peonies.

Peony – Wisconsin Horticulture

Cut Flower Updates: July 4, 2025

Storing peonies to bloom at a later date - MSU Extension