Green manures are used mainly for improving garden soil during the months when one’s garden is not in use. To reap the benefits of green manures, incorporate the green foliage into the soil (while green or soon after dying) to provide biomass to the soil’s upper levels.
Increasing organic matter content - By incorporating the cover crop stems and foliage into the soil, essential particles are added to the soil, which together with the mycelia and the compounds produced by microorganisms form soil aggregates. These aggregates make the soil easy to work, with high water infiltration rate and increased level of organic humus.
Preventing soil erosion - Cover crops provide very good coverage in a very short period of time during the months when the garden is not in use. They reduce water runoff during heavy rain and protect the soil from crusting.
Weed suppression - Fast-growing cover crops take up space and light, thus reducing the opportunity for weeds to establish themselves.
Improved soil tilth - The extensive root systems of cover crops are very effective for loosening and aerating the soil, thereby improving water, root and air penetration, and increasing the soil’s moisture holding capacity.
Increasing worm and microbial activity - After young and lush plants are introduced in the soil as green manure, the soil microbes multiply rapidly to attack the fresh biomass.
Organic nitrogen production - Cover crop mixes containing legumes produce nitrogen, which is an important benefit from using your garden during the winter. The amount of nitrogen produced depends on the crops used, soil pH and the available soil moisture.
Providing aesthetic value and color in the vegetable garden during the winter - In most cases, cover crops are mixes that contain various legumes, which produce attractive flowers in harsh conditions. In turn, this provides good cover and color during the winter in places normally bare and covered in mud. If used in summer months, cover crops provide habitat, nectar and pollen to beneficial insects.