What are Cover Crops? Its Meaning, Types and Benefits

Table of Contents

• What is a Cover Crop?
• Which are the Major Crops Cultivated under Cover Crops in India?
  • Grasses
  • Legumes
  • Non-Legumes
  • Brassicas
• What are the Benefits of Cover Crops?
  • Maintains Soil Health
  • Moisture Control
  • Nitrogen Enrichment
  • Improve Water Infiltration and Retention
  • Promote Microbial Activity
  • Weed, Disease & Pest Management   
• Conclusion

What is a Cover Crop?

Cover crops are non-harvested plants grown to add nitrogen to the soil, prevent erosion and weed growth, and improve biodiversity. Different cover crops include legumes, non-legumes, brassicas, and grasses. A cover crop is cultivated during the off-season before cash crop cultivation to prepare the land. They are used as living mulch between crop rows or as livestock forage.

According to ICAR, the area under cover crops in India is around 1.94 million hectares, and around 1-2 million farmers are estimated to be practicing cover crops.

Which are the Major Crops Cultivated under Cover Crops in India?

Grasses, Legumes, Non-Legumes and Brassicas the major crops cultivated under Cover Crops in India. Let’s have a look:

Grasses

Grasses are an ideal option among all cover crops. The reason is that they have deep roots, which allow them to add organic matter to the soil by breaking the compaction. This cover crop is helpful in controlling soil erosion. It can also be used for other purposes, such as livestock forage. The major crops are:

• Rye
• Ryegrass
• Oats

Legumes

Legumes make an alternative to grasses as popular cover crops. These enrich the soil by providing nitrogen. This nitrogen nutrient helps plant growth. Legumes have deep roots, which can break soil compaction and hold the soil tightly to prevent soil erosion. The major crops include:

• Cowpea
• Sorghum
• Pearl Millet

Non-Legumes

Most of these are suitable for suppressing weeds, preventing soil erosion, building organic matter, and scavenging nitrogen. Some of these cover crops are classified as summer annuals, winter annuals, biennials, and perennials. These improve the soil structure and bind the particles directly through the roots. The major crops are:

• Oats
• Barley
• Wheat

Brassicas

Brassicas cover crops are grown because of their quick growth. These are helpful in reducing soil compaction and suppressing the growth of weeds. These are leafy and offer shade to the soil, which also prevents weed growth. Different brassicas have different root systems and thus can improve soil structure, soil aeration, and water infiltration. The brassicas include:

• Turnips
• Mustard
• Radish

What are the Benefits of Cover Crops?

Several benefits of cover crops include:

Maintains Soil Health

Cover crops help maintain and improve soil health. It reduces water flow, preventing it from carrying fertile soil. It creates obstacles through stems, roots, and leaves that limit water movement, thus maintaining soil health. It helps stabilise soil particles through its roots. One of the main benefits of cover crops is their role in preventing soil erosion. They cover the field and prevent soil erosion from water or wind.

Moisture Control

Cover crops benefit through moisture control, mediating between precipitation and the soil surface. The crop reduces rainfall intensity when it falls on the soil surface. It allows the roots to control the soil's moisture levels without it being removed by the force of falling rain. This moisture control helps the next crop by offering sufficient moisture in the soil.

Nitrogen Enrichment

There are nitrogen-producing cover crops known as legumes that fix nitrogen and reduce the dependency on nitrogen fertilizers later. Legumes are cover crops that fix nitrogen and enrich the soil. They mediate between the soil and the rhizobia bacteria, facilitating nitrogen uptake from the soil. Legumes provide carbohydrates to bacteria, and the soil's nitrogen is released when the bacteria or the crop dies.

Improve Water Infiltration & Retention

Cover crops reduce surface runoff, allowing water to be retained in the soil. It also reduces evaporation, as water is retained in the soil.  The residue helps increase water infiltration. They help maintain suitable soil moisture by absorbing excess water after rainfall.

Promote Microbial Activity

Cover crops promote microbial activities through residue decomposition. When mixed with legumes, they enhance decomposition. This decomposition with a diverse cover crop mixture increases the size of microbial and fungal communities. Different mixtures of cover crops promote varying levels of microbial activity, resulting in increased numbers of living organisms in the soil. This helps make the soil more fertile, which results in improved crop quality.

Weed, Disease & Pest Management

In barren fields without vegetation, there is a higher risk of weed invasion. Cover crops develop a protective layer above the soil that prevents weed and pest invasion. Also, they can block the disease cycle to effectively manage bacterial and fungal diseases.

Conclusion

Cover crops can be an effective tool for achieving sustainable, organic crop production. However, there is a need for suitable research and understanding before deciding on the type of cover crop to choose, as well as the method and timing of cover crop farming. Cover crops are a profitable long-term investment that help ensure healthy soil and higher crop yields.