Mulching is the process or practice of covering the soil/ground to make more favorable 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.

Mulching Film






Advantages Of Plastic Mulching

  • It is completely impermeable to water.
  • It prevents the direct evaporation of moisture form the soil and thus limits the water losses and conserves moisture.
  • By evaporation suppression, it prevents the rise of water containing salts.
  • Mulch can facilitate fertilizer placement and reduce the loss of plant nutrient through leaching.
  • Mulches can also provide a barrier to soil pathogens
  • Opaque mulches prevent germination of annual weeds from receiving light
  • Reflective mulches will repel certain insects
  • 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 system.
  • Synthetic mulches play a major role in soil solarisation process.
  • Mulches develop a microclimatic underside of the sheet, which is higher in carbondi-oxide due to the higher level of microbial activity.
  • Under mulch, the soil structure is maintained during cropping period
  • Early germination almost 2-3 days.
  • Better modulation in crops like Groundnut.
  • Less nematodes population.
  • Water erosion is completely averted since soil is completely covered form bearing action of rain drops.
  • When compared to organic mulches, it serves for a longer period.

Moisture Conservation, Limitations, Areas Of Application

  • 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 irrigations.
  • 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
Mulching is mainly employed for
  • Moisture conservation in rainfed areas
  • Reduction of irrigation frequency and water saving in irrigated areas
  • Soil temperature moderation in greenhouse cultivation
  • Soil solorisation for control of soil borne diseases
  • Reduce the rain impact, prevent soil erosion and maintain soil structure
  • In places where high value crops only to be cultivated

Types & Basic Properties Of Mulch Film

A wide range of plastic films based on different types of polymers have all been evaluated for mulching at various periods in the 1960s. LDPE, HDPE and flexible PVC have all been used and although there were some technical performance differences between them, they were of minor nature. Owing to its greater permeability to long wave radiation which can increase the temperature around plants during the night times, polyethylene is preferred. Today the vast majority of plastic mulch is based on LLDPE because it is more economic in use.

Basic Properties Of Mulching Film :

  • Air proof so as not to permit any moisture vapour to escape.
  • Thermal proof for preservation of temperature and prevention of evaporation
  • Durable at least for one crop season

Importance Of Parameters Of The Plastic Film :
(A) Thickness

Normally the thickness of the film does not affect the mulching effect except when it is used for solorisation. But some of the recent references do indicate the impact of film thickness on crop yield. Since it is sold by weight it is advantageous to use as thin a film as possible but at the same time due consideration should be given for the longevity of the film. The early mulch film used were of 60-75 micron (240-300 gauge) thickness, and today it is possible to have 15 micron thick film due to advent of film extrusion technology. These films are mechanically weak, as shown by their easy tearing when pulled tension.

Width :

This depends upon the inter row spacing. Normally a one to one and half meter width film can be easily adopted to different conditions.

Perforation :

The perforations may be advantageous under some situations and disadvantageous for some other situation. The capillary movement of water and fertilizer distribution will be better and more uniform under unperforated condition. But for prevention of water stagnation around the plants, perforation is better. But it has got the disadvantages of encouraging weed growth.

Mulch Colour :

  • The colour of the mulch affects
  • perature of air around the plants
  • Soil salinity

(a) Due to lesser quantity of water used

(b) Due to reduction in evaporation and prevention of upward movement of water.

Transparent film – Deposits more salt on soil surface
Black film – Restricts water movement and upward movement of salt is reduced. iv.
Weed flora – Black film
Insect control – Opaque while film acts as golden colour and attracts insects

  • The selection of mulches depends upon the ecological situations and primary and secondary aspects of mulching
  • Rainy season – Perforated mulch
  • Orchard and plantation – Thicker mulch
  • Soil solarisation – Thin transparent film
  • Weed control through solarisation – Transparent film
  • Weed control in cropped land – Black film
  • Sandy soil – Black film
  • Saline water use – Black film
  • Summer cropped land – White film
  • Insect repellent – Silver colour film
  • Early germination – Thinner film

  • Orchard/Fruit/Established trees
  • Mulching area should preferably be equivalent to the canopy of the plant.
  • Required size of mulch film is cut from the main roll.
  • Clean the required area by removing the stones, pebbles, weeds etc.
  • Till the soil well and apply a little quantity of water before mulching
  • Small trench could be made around the periphery of the mulching area to facilitate anchoring of the mulch film.
  • Cover the film to the entire area around the tree and the end should be buried in the ground.
  • Semi circular holes could be made at four corners of the film in order to facilitate water movement.
  • The position of the slit/opening should be parallel to the wind direction Cover the corners of the film with 4-6 inches of soil on all sides to keep the film in position.
  • In hard soil, make a trench of 1’x1’x2’ depth on four corners of the mulching area and fill it up with gravel or stones, cover the trenches with the mulch film and allow the water to pass through the mulch to the trenches via semi circular holes on the film

  • Mulch should be laid on a non-windy condition
  • The mulch material should be held tight without any crease and laid on the bed
  • The borders (10 cm) should be anchored inside the soil in about 7-10 cm deep in small furrows at an angle of 45°.

  • Very thin film is used for short duration crops like vegetables.
  • Required length of film for one row of crop is taken and folded in ‘thaan’ form at every one metre along the length of the film.
  • Round holes are made at the center of the film using a punch or a bigger diameter pipe and a hammer or a heated pipe end could be used.
  • One end of the mulch film (along width) is anchored in the soil and the film is unrolled along the length of the row of planting.
  • Till the soil well and apply the required quantity of FYM and fertilizer before mulching.
  • Mulch film is then inserted (4-6”) into the soil on all sides to keep it intact Seeds are sown directly through the holes made on the mulch film.
  • In case of transplanted crops, the seedlings could be planted directly into the hole.
  • For mulching established seedlings, the process of punching the hole is the same. One end of the film along the width is berried in the soil and the mulch film is then unrolled over the saplings. During the process of unrolling, the saplings are 8 held in the hand and inserted into the holes on the mulch film from the bottom side, so that it could spread on the topside.

Precautions for Mulch Laying

  • Do not stretch the film very tightly. It should be loose enough to overcome the expansion and shrinkage conditions caused by temperature and the impacts of cultural operation.
  • The slackness for black film should be more as the expansion, shrinkage phenomenon is maximum in this color.
  • The film should not be laid on the hottest time of the day, when the film will be in expanded condition.

  • Do not stretch the film very tightly. It should be loose enough to overcome the expansion and shrinkage conditions caused by temperature and the impacts of cultural operation.
  • The slackness for black film should be more as the expansion, shrinkage phenomenon is maximum in this color.
  • The film should not be laid on the hottest time of the day, when the film will be in expanded condition.

Mulching Films, Crop Covers, Fruit Covers For Agriculture, Agricultural Mulching Film, Polyhouse Film Manufacturer, Supplier, Trader, Service Provider, Tailor Made Solution Provider, Nashik, Maharashtra, India