Types of Mulch

Many types of mulch or mulching materials exist depending on the preferences, situation, and location. There are two generic types of mulches; organic and inorganic mulch. 

 

Organic mulch is anything that is found in nature and can be broken down by soil organisms. Inorganic mulch is anything man-made, or anything like a rock that cannot be broken down by soil organisms. Inorganic mulches will have a much longer life span than organic mulches, but will usually not have a very natural look or give anything back to the soil.

Organic Mulch

Few organic mulch, which can be utilized as mulch, are described below.

1.                  Bark: These are good organic mulch materials because they retain moisture for a longer period which helps to utilize stored moisture for a considerable period for crop growth. It is commonly used for vegetation and landscaping, but it should be avoided for vegetable fields because it is acidic. It is suggested to use in fields with proper amendments. However, these mulches are excellent for covering the paths between beds.

2.                  Grass Clipping: These are one of the most easily and abundantly available organic mulch materials/ garden mulch in Indian agriculture. If fresh grass clippings are used in the field, it decomposes easily and increases the percentage of nitrogen in the soil. The different types of grass clipping are widely available such as green or fresh and dry grass. Normally, green grass clippings are not used in the rainy season because it may chance to the development of its own root systems or aggravate the termite problems which will be harmful to crop growth. The use of green clippings can heat up soil quite a bit and possibly cause damage to plants. So, always the dried grass always preferred to use as mulch to a depth of 2-3 inches.

3.                  Dry Leaves: Leaves are beneficial for the soil it contributes nutrients when used as mulch. It is widely used in natural forest areas and where trees are plentiful. Dry leaves are easily and abundantly available and it makes better mulch if it is composted. However, dry leaves are not easily available in the spring season; they are valued as overwinter mulch. To restrict the blowing of dry leaves, small branches and wood barks are kept over the dry leaves mulch. The thickness of the dry leaves mulching is about 3-4 inches.

4.                  Straw: Straw mulch is ideal for mulching because it can be easily applied in the field, stays in place and reflects sunlight. Straw mulch is used as winter protection and as summer mulch in vegetable fields. Straw mulch provides great insulation, water penetration, and weed control. The main advantage is that it does not contain weed seeds themselves.  Straw mulches are avoided to use in high-traffic areas due to their highly inflammable properties. The thickness of the straw mulching is about 6 - 8 inches.

5.                  Compost/ Manure: The compost is good garden mulch and soil conditioner. It can easily be prepared or formed at home by composting different types of waste materials like leaves, straw, grass and plant residues, kitchen wastes, garden wastes, etc. The availability and application of compost in Indian agriculture is old age practice. It improves the soil bio-physicochemical properties, enhances the carbon content, improves the soil health and improves the water retention capacity of the soil. The excellent use of compost is at the time of bed preparation or as ‘top dressing’ thinly in the early part of the season. It is used as mulch in some nutrient-loving plants like roses. Apply at a depth of 3-4 inches. One should be aware of using well-decomposed compost otherwise it may aggravate the weed, pest (especially termite), and disease problems.

6.                  Sawdust: Sawdust is a very common type of mulch in areas with the wood industry. It is found during the finishing operations of wood. It has higher nitrogen content. Improper use may lead to serious termite problems due to the higher cellulose content.

Inorganic Mulches

1.            Rock mulch: Mostly used for gaining higher infiltration and reducing soil erosion in the hilly terrace or undulating lands.

2.            Soil or Dust mulch: If the surface of the soil is loosened, it acts as mulch for reducing evaporation. This loose surface of soil is called soil mulch or dust mulch. Interculturing creates soil mulch in growing crops and helps in closing deep cracks in Vertisols.

3.                  Plastic mulch: Both black and transparent films are generally used for mulching. Advancement in plastic chemistry has resulted in development of films with optical properties that are ideal for a specific crop and locations. These are two types.

a)      Photo-degradable plastic mulch: This type of mulch film gets destroyed by sunlight in a shorter period.

b)     Bio-degradable plastic mulch: This type of plastic mulch film is easily degraded in the soil over a period of time. Generally, the following types of plastic mulch films are used in horticultural crops.

                    i.            Black plastic film: It helps in conserving moisture, controlling weed and reducing outgoing radiation. It is most commonly used by farmers especially in Odisha we are using black plastic mulch for vegetable and fruit crops.

                  ii.            Reflective silver film: It generally maintains the root-zone temperature (cooler temperature as compared to atmosphere) and diverts the insect population from the crop plant due to reflective action.

                iii.            Transparent film: It increases the soil temperature and preferably used for solarization purpose.