We often take it for granted that plants have everything they need when we have transplanted them into a new pot or garden, but the truth is that this is not always the case. As we know, all living things need oxygen to breathe , including plants and, of course, their root system.
If the soil or the substrate does not allow the roots to be properly aerated, the plants would weaken and the fungi could seriously harm them. To avoid this, the oxygenation of the roots is very important .
The roots absorb oxygen (O2) and expel carbon dioxide (CO2) in order to carry out their functions. To do this, they need to absorb O2 from water , which is made up of two molecules of oxygen and one of hydrogen (H2O). We could then think that the more we water, the more oxygen it will have but… we would be wrong.
They can only absorb a little water at a time, and the time they need to do so is longer than it takes us to water. In fact, a plant consumes approximately 0.2 to 1mg of oxygen per gram of root every hour . This means that if we overwater, the root system will suffocate and die.
The temperature of the water must also be taken into account, since the higher it is, the less oxygen it can dissolve . For example: if it is 18ºC, the roots will be able to dissolve 9.1mg/l; but if it is 30ºC, the oxygen content in the water will decrease to 7.1mg/l.
Depending on the climate of our area and the season in which we find ourselves, we will have to develop an irrigation strategy in order to avoid attracting diseases and thus ensure that our plants can develop correctly . To do this, what we have to do is use a suitable substrate for each type of plant , and check the humidity of the substrate before watering by inserting a thin wooden stick as far as we can and see if it has come out practically clean (in which case we should water) or not.