I live near Portland Oregon & I want to divide ground peonies & the Brackenhair ferns this year. Thanks for your help!
Peonies & Brackenhair Ferns
Ferns are divided in spring. Here is the how-to article: https://www.gardeningknowhow.com/ornamental/foliage/ferns/how-to-divide-fern-plants.htm
Peonies are divided in fall. There are several YouTube videos showing how to do this. I like the one from Fine Gardening: http://www.finegardening.com/article/how-to-divide-peonies