Deciding whether night irrigation or daytime irrigation is convenient depends on important factors and directly influences the good production of a crop.
Factors influencing night watering or day watering
The suitability in the election is not an easy thing, since it depends on multiple factors:
- De sistema de riego:
- Inundación.
- Aspersión.
- Riego localizado.
- Water quality:
- Dureza del agua.
- Salinity del agua.
- Tipo de cultivo:
- Tolerante a que se mojen sus hojas o frutos.
- No tolerante.
- Soil temperature conditions.
- Losses due to evaporation.
Even placing the factor number 5 in the last place, at this moment it is the one that has the greatest weight. This is due to the fact that most of the irrigations do not have the flow and the sufficient quantity to be able to cover the total water needs of the crop.
For this reason we must try to be as efficient as possible, and hence, carry out night-time irrigation, at which time we limit the losses due to evaporation of the applied irrigation.
If we find ourselves in the opposite case, or we have installed a well-designed localized irrigation system, we will no longer be excessively limited by evaporative losses and we will have more freedom in the hours to choose when to water.
Development of factors that influence night or day watering
Flood: best daytime
With flood irrigation you must water in broad daylight to be able to check that the beds are adequately flooded. Here all evaporative losses are assumed without fear, as there is no limitation in the water supplied. It is applicable to certain crops such as rice and always with abundant irrigation.
Sprinkling: best nocturnal
Using sprinkler irrigation , is when it is most important to handle all the factors in the list at the beginning smoothly. You have to study and be clear about what type of water I am handling and what type of crop I am going to irrigate.
In sprinkler irrigation, nighttime irrigation is highly recommended because at night the wind usually blows with less intensity and does not affect the design of the installation as much. In the same way, the evaporative conditions are lower and the application is more efficient.
Very useful in large areas of lawns, meadows and herbaceous crops.
As we normally do not have aspersion, I am not going to delve into the subject and return to the nuclear issue.
Localized or drip irrigation: favorable diurnal
With localized irrigation the maximum irrigation technology has been reached, this depends on a good design and installation. We can only dampen the useful surface of our crop, and in addition, we control the rest of the factors that intervene in irrigation in a highly effective way.
The importance of the water conditions is no longer so important, since we are no longer going to wet our crops.
In a well-designed localized irrigation there are no waterlogging points, therefore the evaporative factor does not limit us compared to what time we apply irrigation, therefore night irrigation or daytime irrigation is possible.
Influence of subsoil temperature on localized irrigation
And in localized irrigation, if we have the means to do it, factor number four is very important, that is, measuring the temperature of the subsoil . This is due to the fact that as root activity can only develop adequately in a proper interval for each crop, but roughly it is 20-25ºC, if with improper irrigation management we alter these thresholds we can make the crop unable to take advantage of all the irrigation applied.
With nighttime irrigations, it is possible that the nocturnal thermal decrease is added to the decrease caused by the temperature of the applied water, and this induces that during many hours of the day we are outside the adequate temperature range. So we would have moisture but no root capacity to absorb the applied water.
And just at the opposite pole, there would be the benefit obtained from watering during the day and achieving drops in temperature that would cause the wet bulb to descend until it was in the optimal range.
We leave out of this brief summary, as a bird's eye view, other factors such as the price of electricity, the ambient temperature that affects the motors that operate the extraction pumps or the duration and possibility of implementing night irrigation shifts or daytime irrigation.
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