Watering zone times setup

I setup all my zones to water for a certain time, i.e. 20 minutes, however IRO splits that up into two cycles - 10 minutes each. Why does it not run the full 20 minutes and then move on to the next zone?

this is the smart cycling feature. it is providing time for the water in the first 10 minute cycle to soak into the ground, then it runs the next 10 minute cycle. this is the most optimal way to water without waste.

if you have not been doing this in the past, i bet you money your landscape will look better during peak heat.

@raj For the gory details, and exact max runtimes for nozzle/soil/slope combinations.