Get the most from your irrigation system

Water is a big determinant of the success of a crop. But far more than just availability, how water is applied, when, and how much, is nothing short of a science. Lindi Botha spoke to experts about how an irrigation system should be approached for best results.

-  Lindi Botha

With all farming operations, the key objective is to improve yields and quality. This is achieved through nutrition, water, genetics and climate. Focusing on water, a farmer’s chosen irrigation system can make or break his business.

To get the best from an investment in irrigation, a farmer should ensure that the right system is implemented from the start, and then ensure that a proper maintenance programme is in place to keep this investment functioning optimally.

GET THE NUMBERS RIGHT

Hennie Needham, general manager of Rivulis Irrigation in South Africa, says that there are six key considerations farmers must keep in mind when choosing an irrigation system: the type of crop; the climate; the field shape and slope; the water source and quality; soil type; and energy source, availability and any limitations with power supply. “Once all these factors are clear, it will be easier to determine the irrigation need, and therefore the size and individual components required to irrigate optimally.”

With the crop type in mind, the next step is to look at the climate, and in particular the water required to grow the crop in that specific climate. Needham explains that here, precipitation, evaporation, temperature, and wind need to be taken into account.

“With the knowledge of the specific crop you will grow, you need to determine its water requirement, which is measured by evapotranspiration. This in turn, is determined by solar radiation, temperature, humidity, and wind.”