For soil preparation and sowing of green fertilization, it is most ideal to use procedures with a low number of passes, which minimize the loss of soil moisture. The green manure crops can be sown at the same time as the stubble cultivation after the removal of the main crop, so soil preparation does not mean additional costs. Sowing can be done cost-effectively with a grubber equipped with a seed container or a fertilizer spreader, but a direct seeding machine can also be used. Thus, the cost of sowing with the seed - depending on the green manure mixture - is about HUF 20-25 thousand per hectare.
If there is a large amount of stem residue in the area, it is worth spreading 30-50 kg of nitrogen active material per hectare before sowing the green manure crops. In this way, the pentosan effect can be prevented, we can get a better content, a larger green mass, and the plants develop better even in a drier period. The applied nitrogen active substance does not represent an additional cost, as it is returned to the soil with plant residues, so the next plant can utilize it. It is worth choosing the time of sowing according to the regional conditions, from mid-July to the end of August. Apart from extremely dry regions, sowing in August is more common, as it has a more favorable effect on the green mass and content of long-day crops (e.g. mustard, oil radishes). Early sowing, within 1-2 days after harvesting the main crop, is increasingly important in drought regions and dry seasons. The amount of seed, depending on the type of mixture, is usually 15-25 kg per hectare. The recommended amount should not be reduced, as the desired density of plants will not be ensured, weed suppression, ground cover and organic matter formation will not be adequate. Moreover, unnecessary tillage causes even more damage. Most green manure plants have small seeds, can be sown to a depth of 2-3 cm, and these are not segregated in the seeder. Exceptions to this are legumes with large seeds (e.g. peas), which need to be sown deeper.
The time of incorporation of green manure plants must be chosen depending on the mixture. As a rule of thumb, it is worth working into the soil budded or flowering stock. With the exception of butterflies, after flowering, the plants become woody, the C:N ratio increases, as a result of which the decomposition of the rotted plant remains is delayed. If there is a large mass of greens, it should not be turned in in one mass without shredding, because the soil becomes excessively airy. This also makes it difficult to break down organic matter, and it also hinders soil cultivation and the development of the subsequent crop.
Most green manure plants tolerate minor frosts. However, chickpeas are sensitive to frost, while purple clover overwinters. The frozen plant stock can also be used as ground cover mulch. Overwintered plant stock and plant residues left on the surface as mulch should be incorporated in the spring, before sowing.