Farm Management

Crop rotation

The objectives of classic crop rotation and proper crop rotation are very similar. Crop rotation is an established, multi-annual rotation of specifically selected plants and the accompanying cultivation activities in order to increase soil fertility and achieve stable high yields without increasing investment in fertilisation and protection.

However, crop rotation does not take into account the needs of the market and, therefore, by increasing soil quality in this way, we do not ensure the financial stability of the farm. Proper crop rotation that builds soil fertility – in line with the principles of crop succession – is a practical way of reconciling these two requirements. Proper crop rotation is not a closed cycle, but a sequence of successive crops and accompanying measures that enhance soil fertility and enable the farmer to optimise income and costs in the long term.

When establishing the rotation, the following principles should be taken into account to make it correct:

  • plants that take up a lot of nutrients should be followed by plants with lower requirements,
  • shallow-rooting crops (beet, lucerne, clover, rape, legumes) should be grown after crops with a deep root system,
  • after plants that leave a lot of residues (perennial bean plants) – after plants that leave little or no residues (root crops, flax),
  • structure-destroying crops, such as cereals, should be grown after structure-destroying plants (broad beans),
  • plants that reduce pathogen populations (e.g. crucifers that reduce nematode populations) should be followed by plants that increase their populations (root crops).

What we most often encounter in practical agriculture is a flawed, highly simplified crop rotation, set up to minimise current inputs and maximise short-term profit. This results in a deterioration of soil fertility and forces the farmer to continually increase inputs in subsequent years. An extreme version of faulty rotation is monoculture (growing one crop on the same land for many years), leading to a very rapid loss of many soil characteristics that determine soil fertility. Proper crop rotation involves using the soil fertility characteristics already obtained for the current crop and using them to further increase fertility for future crops. The basis of soil fertility is its biological activity, which results from the activity of micro-organisms and the content of organic matter, including humus, in all its forms. The organic matter in the soil is constantly changing, it is the basis for the existence of bacteria, actinomycetes, fungi, etc. and a constant supply of it determines the biological activity of the soil. Therefore, a maximum of crop residues should be left where the plants have grown. Each crop activates a different set of microbes enriching the biological life, it can shade the soil differently, protecting against weed germination, the root systems can influence soil structure differently, the presence of soil nitrogen-fixing microorganisms (e.g. broad bean plants) or reducing the population of certain pathogens (e.g. the effect of cruciferous plants on nematodes). Proper crop rotation relies on a combination of these elements to build long-term soil health and fertility.