Direct sowing is absolutely established in many areas of Spain and it is already a fact because almost all the farmers’ who practice this sowing technique are really satisfied with the results obtained. Therefore, we do not understand why it is not fully consolidated in all areas... the key might be that all areas do not have the same characteristics of soil, climatology, etc. or it may be even be due to the farmers’ culture, as it is necessary to be open-minded and willing to change. Some farmers stay halfway and do minimal tillage, which can also be a good solution.
As we have already said in several articles dedicated to sowing, in our area nobody practices direct sowing, so we went to talk to our friends Fernando (from Medina de Rioseco - Valladolid) and Daniel (from Barchín del Hoyo - Cuenca). Our two friends are great farmers, with large farms of hundreds of hectares in extensive crops that have practiced direct sowing for several years. The conclusion they draw is that the results are very similar to those of traditional sowing and the costs are much lower, especially costs in agricultural machinery and time because the soil preparation task are eliminated and the tasks are limited to sowing, fertilizing and spraying.
One of the dilemmas for the farmer who wants to do direct sowing is the choice of the seed drill machine and, therefore, whether it is with disc or coulter... this is the key piece in this sowing technique. Fernando works with a Gil disc seed drill machine and a Solá coulter seed drill machine. In its field, the disc sower works much better because it does a perfect conservation of the surface layer of soil where the seed is left (the disc opens the soil, deposits the seed and closes; this is a similar operation to that performed by a scalpel). Fernando observes that the seed drill machine with coulter breaks the soil more and in its fields the seed takes longer to germinate.
On the other hand, Daniel tells us that for him the seed drill with coulter is ideal, as they tend to have a lot of clay soil and when sowing, if it is wet, the disc does not work well. Another problem they have is that when the straw (which is chopped by the combine harvester and incorporated as organic matter into the soil) has not decomposed well and is wet, then, the disc is often not able to stick into the soil and the seed remains too shallow. Needless to say, for terrains with a lot of stone, coulters work much better by penetrating better between the stones than the disc.
As we said, the costs are usually lower because the soil preparation tasks are completely removed. It is true that the use of herbicides to control weeds increases, so it is necessary to have a control of its use to not increase costs and pollution. Daniel does an herbicide treatment just before sowing in order to eliminate the few weeds that have been able to be born with the autumn rains. If it does not rain, the recommendation is to wait for the rains or sow as late as possible in order to do a purge of weeds before the sowing.
Versión en español.
