Practical technology for application of catch crops
1. Significance of catch crops
There are several main advantages to catch crops:
- protection against soil erosion - wind and water;
- moisture retention - so valuable for our climate and soil types;
- the temperature of the soil under cover is maintained higher in winter and respectively with higher activity of soil life;
- structuring the soil through the root system at different depths, improving the system of pores and respectively optimizing aeration - severely disturbed in some regions and soils;
- suppression of weeds;
- green manure - binding of nutrients, their accumulation in easily accessible compounds, increasing the content of organic matter, and thus the beneficial soil fauna and in general the construction of humus;
- reduction of mineral nitrogen fertilizer rates, and thus direct visibility of rapid economic benefit;
- some of the crops have phytosanitary properties and purpose - control of soil pathogens and parasites;
There are several main advantages to catch crops:
- protection against soil erosion - wind and water;
- moisture retention - so valuable for our climate and soil types;
- the temperature of the soil under cover is maintained higher in winter and respectively with higher activity of soil life;
- structuring the soil through the root system at different depths, improving the system of pores and respectively optimizing aeration - severely disturbed in some regions and soils;
- suppression of weeds;
- green manure - binding of nutrients, their accumulation in easily accessible compounds, increasing the content of organic matter, and thus the beneficial soil fauna and in general the construction of humus;
- reduction of mineral nitrogen fertilizer rates, and thus direct visibility of rapid economic benefit;
- some of the crops have phytosanitary properties and purpose - control of soil pathogens and parasites;
2. Requirements for catch crops.
To perform their tasks, catch crops must have the following characteristics:
- to be fast-growing and to form a large volume of organic matter - rapid growth and coverage of the soil surface - thus suppressing the development of weeds;
- have a delicate leaf mass, which is quickly mulched to facilitate the sowing of the main crop after it;
- the tender leaf mass mineralizes quickly and feeds nutrients to the first main crop;
- in the mixtures it is recommended to have non-wintering species, which form a lush leaf mass, which after scalding in the winter allows trouble-free mixing with the soil treatments in the spring;
- to form a root system with a large mass and volume;
- the mixtures should have components with different types and depth of root systems, so a multi-layered structuring of the soil is obtained.
To perform their tasks, catch crops must have the following characteristics:
- to be fast-growing and to form a large volume of organic matter - rapid growth and coverage of the soil surface - thus suppressing the development of weeds;
- have a delicate leaf mass, which is quickly mulched to facilitate the sowing of the main crop after it;
- the tender leaf mass mineralizes quickly and feeds nutrients to the first main crop;
- in the mixtures it is recommended to have non-wintering species, which form a lush leaf mass, which after scalding in the winter allows trouble-free mixing with the soil treatments in the spring;
- to form a root system with a large mass and volume;
- the mixtures should have components with different types and depth of root systems, so a multi-layered structuring of the soil is obtained.
3. Types of catch crops
Basically, we can divide the catch crops into the following categories:
а/ according to the term of use - summer and winter catch crops, as the winter ones are often called pre-crops.
б/ according to the vegetation - wintering and non-wintering species
в/ according to the botanical species - legumes, cereals, crucifers and others.
г/ according to their purpose - for green manure or for extraction of biomass for forage, other goals.
Списъкът с видове допустими по ЕНП междинни култури в България е непълноценен, но който иска да принесе полза на своите земи, би проявил творчески подход към него.
As an importer of seeds from the Austrian brand SAATBAU LINZ, Leader Consulting offers forage turnip and sinapis alba as main catch crops, with an active root system that structures the soil and leaves a rich organic mass behind. The underground mass of these plants is about 35% of the formed above-ground vegetative mass. They have a good nematicidal effect.
Other catch crops recommended by us are spring legumes, also buckwheat, phacelia, which will freeze and allow trouble-free pre-sowing preparation for the main crop in the spring.
Basically, we can divide the catch crops into the following categories:
а/ according to the term of use - summer and winter catch crops, as the winter ones are often called pre-crops.
б/ according to the vegetation - wintering and non-wintering species
в/ according to the botanical species - legumes, cereals, crucifers and others.
г/ according to their purpose - for green manure or for extraction of biomass for forage, other goals.
Списъкът с видове допустими по ЕНП междинни култури в България е непълноценен, но който иска да принесе полза на своите земи, би проявил творчески подход към него.
As an importer of seeds from the Austrian brand SAATBAU LINZ, Leader Consulting offers forage turnip and sinapis alba as main catch crops, with an active root system that structures the soil and leaves a rich organic mass behind. The underground mass of these plants is about 35% of the formed above-ground vegetative mass. They have a good nematicidal effect.
Other catch crops recommended by us are spring legumes, also buckwheat, phacelia, which will freeze and allow trouble-free pre-sowing preparation for the main crop in the spring.
4. Basic technological recommendations for forage turnip
а/ sowing date: mid-August - mid-September.Sowing should not be too early so as not to form generative organs, but still not too late, as we strive to get the maximum green mass above the ground and root mass in the soil.
b/ sowing density: forage turnip is sown with approx. 2-2.5 kg / dca at normal merged line spacing.With a very low sowing rate or large row spacing, the plants will start to form roots, which is not our goal. We are looking for the strong penetrating ability of the main root of this plant to structure and loosen our soil in depth. When forming roots or tubers we will have organic mass, but there will be no complete structure.
c/ fertilization: Nitrogen fertilization is practiced in Western Europe approx. 3-6 kg / dca N in order to enhance vegetative growth and form a larger mass. This also makes sense in our conditions, but due to lack of experience it remains to be seen in the coming years whether this fertilization will pay off economically given the drier autumn conditions. I would recommend around 3 kg / dca pre-sowing or as a second option foliar feeding of the catch crop with nitrogen after covering the rows.
In any case, the main fertilization for the next spring crop should be done before sowing the catch crop, this applies to the storage of phosphorus and potassium, if it is practiced.
d/ plant protection: as a cruciferous crop, forage turnips are attacked by fleas and whiteflies, the fight is carried out if necessary. I recommend not to underestimate the control of fleas, as their density will increase in the regions of cultivation and other crops in the crop rotation will suffer. The density and means are the same as for winter oilseed rape.
e/ pre-sowing processing: Pre-sowing processing should create an optimal soil bed for cohesive germination so that no seeds remain in the soil as a weed background. I would recommend the main tillage for the next crop to be done before sowing the catch crop - let's save the plowing and just loosen the soil layer by machines to 20-25 cm, then make a shallow tillage for a leveled and settled seedbed.
f/ post-frost processing of the catch crop: In practice, the main crop can be sown directly on the decomposed plant residues of the preculture. A widely practiced event is the rolling of the frozen field, so the ice crystals scatter in the cells and lead to easier fragmentation of plant debris.
However, I would recommend a pre-sowing treatment - cultivation, mixing plant residues, refreshing the air balance and leveling the field. It is also needed to incorporate pre-sowing fertilizers for the main crop.
Note: In case we have used for intermediate crops wintering, non-freezing deciduous species such as rapeseed, winter peas / vetch and the like, we need a more aggressive system of spring treatments - disking, mulching, etc., which is not always easy in large portions. I also recommend a preliminary rolling with heavy rollers of the plants exhausted from the winter, so it will be easier to handle the treatments. In cereals such as wheat, barley, etc. however, such a rolling would have the opposite effect - positive for their development and if there are any in the mixture - it is better not to roll.
g/ fertilization of the main crop - if the catch crop has managed to develop favorably and has formed a lush vegetative mass, I recommend reducing the active substance nitrogen by 3-4 kg / ha in the main crop. For example, if you fertilize corn pre-sowing with 12 kg / dca N, you can certainly reduce it to 8-9 kg / dca.
а/ sowing date: mid-August - mid-September.Sowing should not be too early so as not to form generative organs, but still not too late, as we strive to get the maximum green mass above the ground and root mass in the soil.
b/ sowing density: forage turnip is sown with approx. 2-2.5 kg / dca at normal merged line spacing.With a very low sowing rate or large row spacing, the plants will start to form roots, which is not our goal. We are looking for the strong penetrating ability of the main root of this plant to structure and loosen our soil in depth. When forming roots or tubers we will have organic mass, but there will be no complete structure.
c/ fertilization: Nitrogen fertilization is practiced in Western Europe approx. 3-6 kg / dca N in order to enhance vegetative growth and form a larger mass. This also makes sense in our conditions, but due to lack of experience it remains to be seen in the coming years whether this fertilization will pay off economically given the drier autumn conditions. I would recommend around 3 kg / dca pre-sowing or as a second option foliar feeding of the catch crop with nitrogen after covering the rows.
In any case, the main fertilization for the next spring crop should be done before sowing the catch crop, this applies to the storage of phosphorus and potassium, if it is practiced.
d/ plant protection: as a cruciferous crop, forage turnips are attacked by fleas and whiteflies, the fight is carried out if necessary. I recommend not to underestimate the control of fleas, as their density will increase in the regions of cultivation and other crops in the crop rotation will suffer. The density and means are the same as for winter oilseed rape.
e/ pre-sowing processing: Pre-sowing processing should create an optimal soil bed for cohesive germination so that no seeds remain in the soil as a weed background. I would recommend the main tillage for the next crop to be done before sowing the catch crop - let's save the plowing and just loosen the soil layer by machines to 20-25 cm, then make a shallow tillage for a leveled and settled seedbed.
f/ post-frost processing of the catch crop: In practice, the main crop can be sown directly on the decomposed plant residues of the preculture. A widely practiced event is the rolling of the frozen field, so the ice crystals scatter in the cells and lead to easier fragmentation of plant debris.
However, I would recommend a pre-sowing treatment - cultivation, mixing plant residues, refreshing the air balance and leveling the field. It is also needed to incorporate pre-sowing fertilizers for the main crop.
Note: In case we have used for intermediate crops wintering, non-freezing deciduous species such as rapeseed, winter peas / vetch and the like, we need a more aggressive system of spring treatments - disking, mulching, etc., which is not always easy in large portions. I also recommend a preliminary rolling with heavy rollers of the plants exhausted from the winter, so it will be easier to handle the treatments. In cereals such as wheat, barley, etc. however, such a rolling would have the opposite effect - positive for their development and if there are any in the mixture - it is better not to roll.
g/ fertilization of the main crop - if the catch crop has managed to develop favorably and has formed a lush vegetative mass, I recommend reducing the active substance nitrogen by 3-4 kg / ha in the main crop. For example, if you fertilize corn pre-sowing with 12 kg / dca N, you can certainly reduce it to 8-9 kg / dca.
5. Basic technological recommendations for sinapis alba
They are the same as for forage turnips, with a difference in the sowing rate - here it can be slightly lower 1 - 2 kg / dca - however, the denser, the better the effect.
They are the same as for forage turnips, with a difference in the sowing rate - here it can be slightly lower 1 - 2 kg / dca - however, the denser, the better the effect.
6. Basic technological recommendations for legumes and other
Legumes are a wonderful precursor and I would recommend that they be used alone as a main crop, as they are also declared as protein crops. However, annual legumes with more leaf mass can also be used as catch crops. For example, aphila type peas will not leave as much organic matter as leafy peas, so it is preferable for this purpose.
The main disadvantage of legumes is that they need a lot of moisture for germination, and this is often lacking in our country at the end of summer, hence the danger of not sprouting well and appearing as a weed in the main crop.
Ако искате да сложите житна култура като междинна, не бих препоръчала това да са пшеница, ечемик, ръж и тритикале, които ще братят силно и ще създадат проблеми при сеитбата на пролетната култура, а освен това няма да се минерализират толкова бързо за да подадат леснодостъпни хранителни вещества. По-добре да се ползват незимуващи житни видове от списъка, дотолкова, че да се изпълнят условията за плащане по ЕНП.
This, of course, does not apply to catch crops, of which the aim is to extract biomass for fodder or others. There we strive for maximum mass and then triticale and rye are the main components.
Legumes are a wonderful precursor and I would recommend that they be used alone as a main crop, as they are also declared as protein crops. However, annual legumes with more leaf mass can also be used as catch crops. For example, aphila type peas will not leave as much organic matter as leafy peas, so it is preferable for this purpose.
The main disadvantage of legumes is that they need a lot of moisture for germination, and this is often lacking in our country at the end of summer, hence the danger of not sprouting well and appearing as a weed in the main crop.
Ако искате да сложите житна култура като междинна, не бих препоръчала това да са пшеница, ечемик, ръж и тритикале, които ще братят силно и ще създадат проблеми при сеитбата на пролетната култура, а освен това няма да се минерализират толкова бързо за да подадат леснодостъпни хранителни вещества. По-добре да се ползват незимуващи житни видове от списъка, дотолкова, че да се изпълнят условията за плащане по ЕНП.
This, of course, does not apply to catch crops, of which the aim is to extract biomass for fodder or others. There we strive for maximum mass and then triticale and rye are the main components.
7. Recommendations for catch crop mixtures
Many ready-made mixtures for catch crops are available in European countries. They are not selected at random, but contain at least 3 components - plants with different types and depths of root system, which loosen and enrich the soil with organic matter at different levels, and the aboveground mass is lush and more complete as a composition. Examples of such mixtures I would suggest: Forage peas, buckwheat and sinapis alba; common vetch, phacelia, forage turnip, etc.