Fungal–bacterial combinations increased plastic mulch degradation, with Aspergillus-based treatments driving up to 3.71% weight loss in polyethylene and ~4.9% in compost conditions, alongside clear chemical changes. UV pre-treatment and mineral oil further accelerated breakdown by improving microbial attachment and oxidation, especially for stubborn plastics. These results show that pairing fungi and bacteria can meaningfully speed up agricultural plastic decay, though even enhanced degradation remains relatively slow for conventional plastics.