Lycium oxycarpum becomes a rounded shrub or small tree of about 2 m in height. The rigid branches are armed with hard spines. New branches grow long beyond dense old foliage, then curve down before side-branches fill up the space around them.
The bark is usually pale grey to creamy brown. There are shiny swellings at the leaf nodes making the stems lumpy. The leaves are long and narrow.
This thriving plant was seen in April, before the rainy season near Van Wyksdorp in the southern Little Karoo (Vlok and Schutte-Vlok, 2010; Coates Palgrave, 2002).