In reality, it is best to add moisture sensors in each hydro-zoned location since each zone characteristic is a little different. Rachio doesn’t allow for that though.
You could add just one in an area that best resembles most of the other zones.
The Toro sensor acts like a rain sensor and triggers a common disconnect or connection depending on the soil moisture threshold.
My experience with them has been negative. Sometimes the data seems inconsistent and moisture can get into the housing.