If you are happy with the plant health, and the previous setting of 65 minute run time, the easiest way to change the duration is select schedule, then choose the schedule you wish to change, tap on that schedule, then select duration.
To understand more in depth, check this article from the Rachio knowledge base.
An important factor is the precipitation rate. I have some fruit trees that run for an hour, so they are deep-watered, but the frequency is only once a week.
The WUCOLS database does indicate the water requirement for Berkley Sedge is low - moderate, but these plants are tolerant of moist or dry soils.
Initially, it may take bit to get your drip set up properly with varied plant types, but once you do, its terrific to know Rachio is on the job and you don’t have to worry.
As you said earlier @zinarr, monitor and see how it goes. 