Stem constrictions at old nodes on a Psilocaulon junceum plant are variably spaced, sometimes very closely together as seen in the photo. Close spacing of the marked indentations may indicate challenging growth phases or harsher climatic conditions.

These plants tend to carry their proper leaves for short periods only, ending up with much bare stem on display. The young stems are grey-green, about 5 mm in diameter; old ones becoming woody (Vlok and Schutte-Vlok, 2010; Smith, et al, 1998; iSpot).