Cover crops are important because they can suppress weed growth. When fields are left bare, weeds can easily grow and compete with crops for nutrients, water, and sunlight, reducing yields. However, cover crops can help prevent weeds from growing by shading the soil and competing with them for resources. This can result in better crop yields and a healthier soil ecosystem. Additionally, cover crops can improve soil health by adding organic matter, increasing nutrient availability, and preventing erosion.