Mulching is the process or practice of covering the soil/ground to make more
favourable conditions for plant growth, development and efficient crop production.
Mulch technical term means ‘covering of soil’.
While natural mulches such as leaf, straw, dead leaves and compost have been used for centuries, during the last 60 years the advent of synthetic materials has altered the methods and benefits of mulching. The research as well as field data available on effect of synthetic mulches make a vast volume of useful literature.
When compared to other mulches plastic mulches are completely impermeable to water; it therefore prevents direct evaporation of moisture from the soil and thus limits the water losses and soil erosion over the surface. In this manner it plays a positive role in water conservation.
The suppression of evaporation also has a supplementary effect; it prevents the rise of water containing salt, which is important in countries with high salt content water resources.
Advantages of plastic mulching
1. It is completely impermeable to water.
2. It prevents the direct evaporation of moisture form the soil and thus limits the water
losses and conserves moisture.
3. By evaporation suppression, it prevents the rise of water containing salts.
4. Mulch can facilitate fertilizer placement and reduce the loss of plant nutrient through
5. Mulches can also provide a barrier to soil pathogens
6. Opaque mulches prevent germination of annual weeds from receiving light
7. Reflective mulches will repel certain insects
8. Mulches maintain a warm temperature even during nighttime which enables seeds to
germinate quickly and for young plants to rapidly establish a strong root growth
9. Synthetic mulches play a major role in soil solarisation process.
10. Mulches develop a microclimatic underside of the sheet, which is higher in carbondi-oxide due to the higher level of microbial activity
11. Under mulch, the soil structure is maintained during cropping period
12. Early germination almost 2-3 days.
13. Better nodulation in crops like Groundnut.
14. Less nematodes population.
15. Water erosion is completely averted since soil is completely covered form bearing
action of rain drops.
16. When compared to organic mulches, it serves for a longer period.
• Plastic film with its moisture barrier properties does not allow the soil moisture to
escape Water that evaporates from the soil surface under mulch film, condenses
on the lower surface of the film and falls back as droplets.
• Thus moisture is preserved for several days and increases the period between two
• The irrigation water or rainfall either moves into the soil thru holes on the mulch
around the plant area or through the un-mulched area.
• Black plastic film does not allow the sunlight to pass through on to the soil
• Photosynthesis does not take place in the absence of sunlight below black film
hence, it arrests weed growth