Answer: Hostas are best divided in early spring as they are coming up, or in the early fall. Dig up the clump with roots intact, then slice straight down to separate the mass. I try to divide mine into sections with both shoots and roots attached. You can also use a sharp spade or a knife to divide the rootmass. In my experience, a chunk of hosta about six inches square will usually make a nice plant by the end of the summer.
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