Hardy, heat-loving perennial named for knees at its leaf
nodes, showing tiny greenish flowers on spikes in summer. This China
native has naturalized throughout the subtropics.
Grow specs: 2-3 ft. Full sun. 1-2 ft. apart.
Ordinary garden loam. Traditionally used to strengthen liver and
kidneys, as well as supporting muscle and bone structure. Contraindicated
for use during pregnancy.