Like cane, shrub and other stem cuttings however, you do have to use cutting with nodes. Rhizome cuttings can be made any length.
In the illustration the rhizome is cut into two inch sections. Most rhizomes can be rooted directly into your potting mix without any special considerations.
The rhizome is fleshy and can easily maintain inself until roots and leaves form. Some more delicate varieties such as rexes may do better if rooted in an enclosed container though.
Long rhizomes can even be rooted in water like you would any stem cutting. They are slightly more prone to rotting in water though since they are so fleshy.
Although leaf cuttings on rhizomatous types will give you more plants in the long run, rhizome cuttings will give you a new plant faster.
It’s a good method for those that just want another plant or two and aren’t worried about producing larger numbers of plants. The rhizomes don’t have to have leaves to root and grow.
When using the tips of rhizomes remove the largest leaves, they’ll probably fall off during rooting anyway. Make sure the rhizome has good contact with the rooting medium but not buried more than half way.
Tip cuttings from rhizomes can be rooted upright with the cut end stuck one half to one inch into the rooting medium.
Credits / references:
Brad Thompson | Brad’s Begonia World