Legumes as a pillar of nitrogen supply in organic farming
Nitrogen fixing by legumes is the only way to bind elementary nitrogen from the air, making it available to the plants and feeding it into the system.
When growing legumes, crops are usually divided into fodder crops (e.g. clover or alfalfa), catch crops (such as vetches), and grain legumes (e.g. field beans, peas or soybeans). In addition to the direct marketing of the crops produced, further economic aspects come to the fore. These include improving the soil system, maintaining soil fertility and supplying vital nitrogen.
This means that many organic farms use the enormous potential of various fine legumes.
For example, integrating a perennial grass-clover mixture into the crop rotation is becoming increasingly important.
Such stock may be sown both in isolation or under covering cereals.
Where possible, cooperation is sought with dairy farms that use the first and/ or second growth as feed. Subsequent growths are strip-tilled to improve the soil by means of back-flowing biomass.
Other positive characteristics, such as increased biological activity, improved tilth and in particular weed suppression are essential for crop rotation.
The remaining root mass and the rest of the plant provide a direct source of nitrogen for the subsequent crops.
In order to close the material cycles, plants have to be supplied with nitrogen.
Only legumes, as a key pillar of organic farms, are able to fix the required amounts of nitrogen. Depending on the type of crop and the year,
50-700 kg of nitrogen per hectare can be fixed per year. The amount may vary depending on the region. A prerequisite for successful symbiosis (nodulation) between a plant and bacteria is the presence of specific bacterial strains. Our Rhizofix® liquid inoculant can ensure nodule formation and the resulting nitrogen fixation in all common legumes. This is guaranteed by an inoculant that has been specially developed for each crop and contains the required bacterial strains. The Research Institute of Organic Agriculture (FiBL) has included Rhizo-Fix® in its 2017 resource list. It also complies with the Demeter, Gäa, and Naturland guidelines.
Another way to anchor the rhizobia on the seed is by using coated seed. This can be done with all fine legumes. The treated seed contains biological plant strengtheners approved for organic farming and the required bacterial strains. Coated seed is therefore ready to use immediately and does not require additional effort. Coated seed also meets the required organic standards. It has therefore been approved by the inspection bodies for use in organic farming. Such coating is not possible in the case of coarsegrained legumes.
Seeds should be inoculated with RhizoFix® immediately before sowing to ensure successful nodulation and thus nitrogen fixation. There has been another important development in organic farming – the expansion of Category I. It includes varieties registered since 2014, such as maize, sugar beet, white mustard, buckwheat, common vetch and one-year ryegrass. In 2015, Italian ryegrass, winter rye, Egyptian clover, Persian clover and sainfoin were included in Category I. Crimson clover followed on 01/01/2016. Other varieties, such as perennial ryegrass and red clover, are currently under discussion. We want to achieve our objective of supplying the market with good, organically grown seed.
Organic seeds Legumes as a pillar of nitrogen supply in organic farming Nitrogen fixing by legumes is the only way to bind elementary nitrogen from the air, making it available to the