Advances in the Sustainable Use of Plastics in Horticulture—Perspectives, Innovations, Opportunities, and Limitations

Abstract

The use of plastics in horticulture is reviewed with respect to its sustainability based on the traditional criteria of triple Rs (reduce, reuse, and recycling) plus a re-place strategy, taking into account possible alternatives. Hail (and insect) nets made of HD-PE, with their long-term use mostly on apple and polytunnels of LD-PE for cherry and strawberry as well as solarisation mulches (reuse), were found to be relatively sustainable solutions for their needs and are currently without alternatives. In contrast, standard black mulch, with its largest share among horticultural plastics, had the widest range of sustainable alternatives, ranging from biodegradable to spray mulch; few sustainable alternatives are available for fleeces and reflective mulches. For the third sustainable option, pilot recycling schemes were examined, such as PolieCoTM (Italy), MAPLATM (Spain), and ERDETM (Germany); they collect 30–50% of the agricultural plastics used in their respective areas, with a successful retrieval growth rate of ca. 20% per year in the case of ERDETM. For the fourth new R option (replace), future sustainability perspectives for the predominant black mulch are research into and development of better, biodegradable, non-fossilbased plastics, sprayable mulch; microbes for the digestion of deployed polyolefins and, for a certain limited range (on shade tolerant crops or in high-light intensity environment), hail nets and polytunnels that are equipped/substituted by/with solar panels (“agri pv”) for the concomitant sustainable production of green renewable energy.

Plastic Pollution in Agriculture as a Threat to Food Security, the Ecosystem, and the Environment: An Overview

“…Generally, plastic waste mitigation strategies vary across locations globally. Many stakeholders consider that the adverse effects can be prevented using the "R" model (Refuse, Reduce, Redesign, Reuse, Recycle, and Recover) [295][296][297]. It can also be mitigated using the following recommendations:…”

“…A substitute for agricultural development that prevents the buildup of MPs and NPs in soils might be bioplastics, particularly biobased and biodegradable ones [302,303]. Blanke [297] reported that many publications have addressed using substitute biodegradable polymers for the cultivation of several crops, primarily for short growing cycles on bare soils, although they are inappropriate for use as long-term coverings over uneven terrain. Their primary ecological and practical benefit is that they can be buried in the ground and left in the field for microorganisms to break down.…”