What is the maximal area that can be irrigated with a single controller?

A single controller normally irrigates a size of a field covered by a single valve.

In practice there are various consideration that dictates what actually is the

size of a plot that is controlled by a single valve: technical consideration can

limit the size of a plot (i.e. rate of water delivery), topography limitation and

uniformity of soil and plant size. Where there are no limitations on plot size, a

single controller/valve can irrigate as much as 20 ha.