Provided are purified Cannabis hurd fiber, and refined Cannabis hurd fibers, and methods for preparing cellulosic fiber from the hurd of Cannabis plants. The methods include decorticating the bast from the hurd, at least partially fibrillating the hurd fibers, abiotic retting of the hurd fibers, and exposing the hurd fibers to synthetic sunlight and ozonation to produce a purified hurd fiber. The purified Cannabis hurd fibers are substantially free of bast fiber, and have little to no pectin. Also provided are compositions containing the Cannabis hurd fiber or refined Cannabis hurd fiber, including packaging products, molded pulp cartons such as egg cartons, smoking papers, paper packaging materials, single ply or multi-ply paperboard, absorbent paper products and ink receptive papers.