Unique Layered Mulching at Haritachala

Written by Tanvi Pothireddy

Mulching is the process of covering the soil with organic material. Here at Haritachala, we use a unique method called layered mulching. Layered mulching is a technique used in gardening and agriculture to enhance soil fertility, moisture retention, and weed control by applying several layers of different materials on the soil's surface. At Haritachala, our mulching process employs three different materials: dry leaves/thin twigs, green material, and dried stems/branches. 

The first (bottom) layer of the layered mulching process consists of dry leaves and thin twigs. This lightweight material decomposes quickly, making it a perfect first layer. The second (middle) layer, also called the green layer, helps provide nitrogen to the plant and has a lot of moisture. Here, we use gliricidia, a nitrogen-fixing plant grown on our farm. Using a shredder, we shred the gliricidia into small pieces before using it. There are two reasons for the green layer to be the middle layer. First, the moisture in the green material seeps into the first layer, aiding in the breakdown process. This is similar to spraying water on vermicompost.

This water makes it easy for the earthworms to eat and speed up decomposition. In a way, the moisture in the green material helps the dry leaves decompose faster. Second, if the green material is not protected, the water inside it will evaporate. To retain this moisture, we cover the green layer with the brown layer. Additionally, the heavy brown layer helps to prevent the green and dry layers from scattering in the wind. These are the two key benefits of sandwiching the green material. An additional point is that gliricidia has antiseptic and antibacterial properties, which makes sure that adding green material to small plants doesn’t cause root rot. If gliricidia is not readily available, another nitrogen-fixing plant called jatropha, also known as Mexican sunflower, can be shredded and used.

Finally, the third (top) layer is composed of shredded dried stems or small branches. This layer is called the brown material and is heavier than the first two layers. It provides the carbon component to the plant. It is important to follow this sequence when applying the layers, as the light leaves decompose more quickly.

Ideally, we want to layer the mulch as thickly as possible while being careful not to cover the stem of the plant too much. The thicker the layer, the more challenging it is for weeds to emerge. 

Experiment: We first implemented the layered mulching technique on one plant. Let’s compare its soil condition with that of a normal plant. 

Results: 

Plant without mulch: There is a lot of weed growth. Also, the soil around the plant is dry and hardened, devoid of any moisture. It is parched and crumbly, without a single living organism in sight. We can conclude that this soil isn’t alive. 

Plant with mulch: While there is an abundance of weeds surrounding this plant, logic dictates that the immediate area around the plant, too, should have them. Near this plant, though, there were only two weeds. When the layers of the mulch were removed, it was observed that the green gliricidia leaves were completely black and turning into compost while still retaining some moisture. Even though the plant wasn’t watered in a week, it still contained moisture. When another layer was removed, we saw that the soil beneath the bottom layer had so much moisture that it could even be made into a dough-like ball. There was also a diverse range of small creatures in the soil. We can conclude that this soil is nutrient-rich and very alive.

In conclusion, layered mulching is a great technique for reducing weeds, retaining moisture, and maintaining healthy soil.