Knowledgebase
When to divide astilbes #917459
Asked September 14, 2025, 11:03 AM EDT
Hennepin County Minnesota
Expert Response
Autumn is a good time to divide spring and summer blooming perennials, including astilbes. I would wait until our temps go down a bit - even later this week. The heat is hard on them so try for a cloudy or overcast day, hopefully just before a good rain is expected.
https://extension.umn.edu/planting-and-growing-guides/dividing-perennials