Protect the fertility of your soil by using crop rotation

This is an old gardening technique dating back several centuries, and crop rotation was already used during the Mayas for potato growing. It protects the fertility of your soil and avoids the proliferation of certain parasites by moving your crops. 

Indeed, if you sew plants from the same botanical family in the same location for several successive years, you face two major risks :

  • The creation of land propitious to the development of parasites and illnesses specific to this plant.
  • Exhaustion of the soil, as each crop has its own qualitative and quantitative requirements in terms of nutrients.

In line with its requirements, each family of plants will therefore seek the nutrients in various layers of your soil. Some vegetables, such as carrots, turnips or salsify for instance, have roots which will dig deep. However, other vegetables, such as salads, assimilate nutrients more towards the surface.

The crop rotation method

So as to avoid your soil from becoming worse over time, you should practice crop rotation in your vegetable  garden in line with their respective families. The purpose is to not have the same family of plants in the same place within three or four years.
If, for instance, you grow vegetables which require a vast quantity of nutrients (potatoes, beetroot, courgette, leek, cabbage, maize), you should then grow vegetables which will enrich the soil (beans, peas) or which are less greedy (garlic, shallots, onions).

So as to be effective, crop rotation will require a certain amount of organisation. You should first list all the vegetables you want to grow, and then group them by botanical family. The below table will help you to identify these.

Once you have done your sorting, you can then plan the crop rotation for your vegetable garden. 
For a 4 year crop rotation, divide it into   4 plots with an equal surface area. Subsequently, group each family over a dedicated surface area. 

Solabiol Tip :

So as to benefit from plant associations, consider grouping together at least 2 families which "like each other" in the same plot when organising your rotation.

Special case of living plants

Living plants, such as strawberries, asparagus or artichokes can remain in the same place for several years. They are not taken into account by the crop rotation schedule as your other plants.
To regenerate these, you can replant them after a certain number of years and wait before replanting in the same place. The number of years necessary will depend on the type of plantation :

  • Asparagus should not be planted for over 8 years in the same location and you should wait at least 5 years before replanting in the same place
  • Artichokes should be moved after 3 to 4 years.
  • Strawberries should be moved after 3 years and you should wait 5 years before replanting in the same place.