Plastic mulch is a product used, in a similar fashion to mulch, to suppress weeds and conserve water in crop production and landscaping. Certain plastic mulches also act as a barrier to keep methyl bromide, both a powerful fumigant and ozone depleter, in the soil. Crops grow through slits or holes in thin plastic sheeting. Plastic mulch is often used in conjunction with drip irrigation. Some research has been done using different colors of mulch to affect crop growth ( plastic color masterbatch will be used in the film for dyeing, and filler masterbatch will reduce the production cost effectively). This method is predominant in large-scale vegetable growing, with millions of acres cultivated under plastic mulch worldwide each year. Technologies exist to provide for the recycling of used/disposed plastic mulch into viable plastic resins for re-use in the plastics manufacturing industry.
The use of plastic mulches along with the use of drip irrigation has many benefits such as:
Earlier planting dates:
The use of plastic mulch alters soil temperature. Dark mulches and clear mulches applied to the soil intercept sunlight warming the soil allowing earlier planting as well as encouraging faster growth early in the growing season. White mulch reflects heat from the sun effectively reducing soil temperature.
Soil moisture retention:
Plastic mulches reduce the amount of water lost from the soil due to evaporation. This will reduce the water waste. Plastic mulches also aid in evenly distributing moisture to the soil which reduces plant stress.
Plastic mulches prevent sunlight from reaching the soil which can inhibit most annual and perennial weeds. Clear plastics prevent weed growth.
Reduction in the leaching of fertilizer:
The use of drip irrigation in conjunction with plastic mulch allows one to reduce leaching of fertilizers.
Improved crop quality:
Plastic mulches keep ripening fruits off of the soil. This reduced contact with the soil decreases fruit rot as well as keeps the fruit and vegetables clean.
Reduction in soil compaction:
The plastic mulch covering the soil decreases the crusting effect of rain and sunlight. The reduction in weed quantity means a decreased need for mechanical cultivation. Weed control between beds of plastic can be done using directly applied herbicides and through mechanical means. The soil underneath the plastic mulch stays loose and well aerated. This increases the amount of oxygen in the soil.
Reduction in root damage:
The use of plastic mulch creates a practically weed free area around the plant, removing the need for cultivation except between the rows of plastic. Root damage associated with cultivation is therefore eliminated.
Due to these factors, the use of plastic mulch can lead to an improvement in the overall growth of the plant.