Green manure

Green manure is a natural method for soil improvement in agriculture and horticulture.

Effects of green manure

The cultivation of crops for green manure caused by the shading of the soil entering a balance to temperature fluctuations. At the same time the force of the impact of raindrops is reduced, thus opposed to a silting and crusting of the soil surface. By hereby associated improvement of the living conditions of soil organisms Garezustand of the soil and the growth conditions of the crop to be improved. Intensive improve root penetration of the soil by green manure crops and promotion of the soil crumbs building soil organisms and stabilize the soil structure; by growing deep -rooted plants such as lupins or sunflower even compaction in the subsoil can be combated. Especially in sugar beet cultivation of mustard or radish in the form of green manure is also used to control nematodes ( Rübenälchen ) by biofumigation.

The green manure has few disadvantages, such as the additional costs due to the addition usually falling in working peak seed and potential problems in the later incorporation of plant residues.

Green manure supported the formation of humus and is effective against soil erosion and the leaching of plant nutrients from the soil. Through the use of fast-growing plants unwanted weeds and volunteer cereals can be suppressed, an important function in the context of no-till direct seeding cultivation method. In the cultivation of legumes such as peas, beans, clover, vetches and lupins, the soil is also enriched with nitrogen ( the next to be fitted crop are around 30-40 kg nitrogen per hectare additionally available ). Since fertilization with mineral nitrogen fertilizers ( fertilizer ) is not allowed in organic farming, there is an important item of the legume nitrogen source

In livestock- holding farms also a use of green manure crops comes as an additional food source considered. Here, especially the cultivation of clover is due to its high protein content, which in fattening livestock is essential. In addition, wearing clover ( a legume) equal at the input of nitrogen into the soil.

Green manures and crops

For green manure following plant species ( for example, Landsberger mixture ) are mainly singly or in mixtures used: cruciferous vegetables such as white mustard, rapeseed or oil radish, legumes such as lupins, vetch or clover, grasses such as Italian ryegrass and other species such as sunflower or Phacelia. In the selection of green manures the intended crop rotation is observed, the seeds of cruciferous about before the cultivation of cabbage is not displayed because of the promotion of the spread of typical diseases such as clubroot. As far as the green manure crops such as Phacelia collapse during the winter cold period, that is, freeze off, the plant residues after the winter can either remain as a mulch layer on the soil surface or be under worked. In winter hardy species however, it is common for this to work or under at least to shred for example with a mulcher, so that a second growth of green manure crops is prevented in the following crop in the coming growing season before the onset of the cold period.

The cultivation of green manure can be used as main crop undersown or take place over time between the actual main crops as intercrop. However, a growing as a main crop, thus waiving an actual harvest in the crop year is common only in newly cultivated soils (eg, reclamation areas).