Recycled Waste Paper as a Landscape Mulch Open Access

Two studies were conducted to evaluate recycled waste paper mulch for landscape plantings. In the first study, two recycled paper products (pellet and crumble) were applied at three depths. Application of recycled paper mulch at a depth of 25 or 50 mm (1 or 2 in) controlled prostrate spurge. However, in experiment 1, all four bedding plant species exhibited stunting of roots and shoots. In the second study, three annual species were mulched with the two recycled paper products applied at 25 mm (1 in) depth and treated with phosphorus (P) at 0, 3.75, or 7.5 mgL⁻¹ (ppm) to bind suspected excess aluminum (Al). When no P was added, growth of ageratum was approximately half that of the non-mulched control plants. Addition of P at either rate resulted in similar growth compared to control plants. Shoot dry weight of geranium was greater than that of the control plants with 7.5 mg L^−l of P. Shoot dry weight of marigold was unaffected by the addition of P. This research indicates that recycled paper mulch at a 25 mm (1 in) depth, provides weed control equal to or better than standard landscape treatments, and causes little or no growth suppression when amended with P.