Answer: In my experience you can dig up the entire clump and then cut it or pull it into portions with each piece having some top stems and corresponding roots (meaning separate it into clumps of several crowns each), or you can divide the clump while it is still in the ground by cutting straight down with a sharp flat spade, leaving part of the parent plant intact in place if desired. Divisions taken from the outer portion of the plant seem to be more vigorous than those taken from the older center part of the plant; you can make divisions as large or small as you can handle, a nice plant will result from sections about four inches in diameter but a single crown will eventually grow into a nice plant. The best time to do this is in early spring just as the plant is beginning to grow but it can be done at other times if you are very careful to keep it watered afterward. Replant the pieces at the same depth as they grew before, and keep them well watered while they become established in their new location.
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