The popular mini-Sinningias are members of this group. This group of plants also has a type of underground storage mechanism. Rhizomes form along the roots and are renewed each growing season. Rhizomes have overlapping scales that resemble those of a pine cone. Most rhizomatous gesneriads have a dormant period, just like their tuberous relatives.
Rhizomes can also form above the soil level.
These are called propagules. This illustration shows a Kohleria rhizome. Most gesneriads fall into this classification. Although the above two groups have fibrous roots in addition to tubers or rhizomes, this group lacks any type of storage organs. Many of the plants in this classification should never have completely dry soil.