This work assesses the potential of nettle (Urtica dioica L.) ﬁbers produced on contaminated lands for composite applications. The nettles studied in this work grew spontaneously and in a prevalent manner in poplar short rotation coppice planted for the phytomanagement of a land contaminated by traces of metals. Results show that the contaminant contents in nettle bast ﬁbers are low: only traces were mea-sured. It makes it possible to consider this biomass for material use. The measured matter yield is lower than those obtained with traditional ﬁber crops cultivated in Europe on agricultural lands but the tensile properties of the bast ﬁbers are equal to or better than those of hemp and ﬂax, making spontaneous nettle an interesting supplement to traditional European ﬁber crops for composite applications.