Green manure: technique for fertile and healthy soil
NEWS · 21 February 2025
Green manure is an ancient but still relevant agricultural practice that contributes significantly to soil health and fertility.
This technique, based on sowing and burying specific crops, brings numerous benefits, including enriching organic matter, improving soil structure and promoting biodiversity.
With a view to sustainable agriculture that respects the environment, green manure proves to be a winning weapon for farmers who wish to obtain quality production while fully respecting nature.
Zanon, a leading manufacturer of Made in Italy agricultural machinery, has always been attentive to the needs of farmers and offers a complete range of solutions to simplify and optimise the practice of green manure.
Weeding and grassing: let's clarify
There is sometimes confusion between weeding and grassing. While grassing is a generic term for covering the soil with vegetation, weeding is a specific type of grassing in which plants are sown with the specific aim of being buried to enrich the soil with nutrients, which we will examine later in the article.
Weeding, on the other hand, can have different purposes, such as controlling weeds or protecting the soil from erosion.
When and what to sow?
The choice of sowing period and weeding crops depends on the specific needs of the soil and the objectives to be achieved.
- Spring/summer weeding: this is done in spring or summer, using leguminous crops (e.g. clover, vetch) or brassicaceous crops (e.g. mustard, horseradish).- Autumn/winter weeding: in autumn or winter, using grasses (e.g. rye, oats) or cruciferous crops (e.g. mustard, turnip rape).
Weeding crops: a world of biodiversity
Weeding crops are many, each with specific characteristics and functions. Let us look at them in detail:
- Leguminous crops: such as field beans, clover, vetch and lupin, are true nitrogen factories. Thanks to their ability to fix atmospheric nitrogen, they enrich the soil with this essential element for plant growth.- Grasses: such as oats, rye and barley, are excellent allies for controlling excess nitrogen and protecting the soil from the cold. They are often used in combination with legumes to create positive synergies.
- Cruciferae: such as rapeseed, mustard and turnip rape, are characterized by their rapid growth and ability to assimilate phosphorus in the soil in forms otherwise unavailable to plants. They also contribute to improving soil structure due to their deep root system.
How to implement weeding with Zanon machinery
Describing the various types of crops and their functions, we analyse the different stages to implement green manure, discovering in particular which machines can be used in each stage of the process.
Step 1: sowing the crops
After choosing the most suitable crop for the type of soil, sowing is carried out. Weeding green manure is a crucial operation to ensure a successful technique. It is important to distribute the seeds evenly and at the right depth to encourage homogeneous germination and lush crop growth.
The seeders designed by Zanon, thanks to their precision and reliability, make it possible to regulate the quantity of seeds of green manure crops evenly and at the right depth, ensuring homogeneous and luxuriant germination.
Step 2: burial
Green manure planting is a delicate phase that requires care and attention. It is essential to incorporate the crops into the soil at the right time to promote decomposition and soil enrichment.
At this stage, one of the most suitable agricultural machines is the rotary tiller, which is perfect for incorporating green manure crops into the soil, finely chopping up the biomass and promoting decomposition.
Power harrows are also useful at this stage. They work the soil effectively, burying the green manure and creating the best conditions for subsequent sowing.
Fase 3: gestione della biomassa (opzionale)
In some cases, prior to burying, it may be useful to chop green manure crops to facilitate their decomposition and incorporation into the soil. We recommend chopping green manure crops before burying them in the presence of:1. Crops with high vegetative growth: when green manure crops reach a considerable height or produce a large amount of biomass, prior chopping facilitates burial and subsequent decomposition. By chopping the plants, the volume of the plant mass is reduced, making it easier to manage and incorporate into the soil.
2. Presence of woody stems: some green manure crops, such as sunflower, develop woody stems that decompose more slowly. In these cases, chopping accelerates the decomposition process, promoting faster mineralisation of organic matter and nutrient availability for subsequent crops.
3. Limited time for soil preparation: when time for soil preparation is limited, chopping green manure helps to speed up burial and decomposition, allowing the next crop to be sown more quickly.
4. Soil conditions: in heavy soils or soils with high moisture content, preventive green manure chopping can improve soil aeration and prevent waterlogging, promoting biomass decomposition and the growth of subsequent crops.
5. Weed management: in the presence of weeds in green manure, chopping helps reduce their spread, preventing seed production and facilitating control during subsequent soil tillage.
Mulchers or wood chippers can be used to chop the crops before burying them. They transform the biomass of the green manure into organic material that can be used as fertiliser or soil conditioner.
The machinery stands out for its construction quality, robustness and reliability, characteristics that make them valuable allies for all those who want to practice green manure.
The company constantly invests in Research & Development, entrusting its team of experts with the innovation of existing products and the development of new solutions, so that they are ever more efficient and meet future customer expectations. This is demonstrated by the numerous patents in the field of agricultural and electronic machinery production.
Choosing Zanon means choosing quality and innovation at the service of sustainable agriculture. Contact us to find out about all Zanon's green manure solutions and receive personalized advice