A method of forming a support pole, comprising splitting one or more canes of bamboo, or similar tubular plant material, into a plurality of split lengths; inserting a bundle of the split lengths from one or more canes into an outer tube (4); tilting the outer tube (4) at an angle from horizontal and injecting a matrix material into the outer tube (4) so as to fill in between the split lengths and encapsulate the split lengths to form a substantially solid core. The method may comprise injecting the matrix material at multiple injection points (25a, 25b, 25c, 25d) along the length of the tube (4).