Propagating by rhizome is the easiest way to get more ferns. First, locate the fern's crown—this is where the fronds meet in the middle. Then, using a clean knife, cut through it.

Ferns that spread from an underground root (rhizome) are even easier to propagate. Dig up the parent fern. There will be a spreading rhizome. Cut the rhizome where there is at least one frond ...

As a single fern grows, the rhizome may break and produce new fronds. Over time, this creates a colony of ferns. In the spring, new fronds, called fiddleheads, unroll as they grow.