I have a hose-based irrigation system (actually, four zones tied to three spigots: garage, patio, rooftop deck) for my townhouse in Chicago.
If I were going to integrate with a hose-based system, I’d have a controller like the Rach.io system (geo-based, monitoring weather, temp, etc) and then tie in the in-line hose solenoid/flow meter via ZWave/Zigbee/WiFi.
To save energy on the solenoids, I’d probably have a button that enabled the connection for 5 minutes for programming, and then otherwise checked in every couple (6?) hours for updates. That said, a power box that could control a couple solenoids at once and plugged into a wall jack would work too.
The controller could potentially be tied into a home automation system like SmartThings, IFTTT (not ideal since there are no compound triggers e.g. time + weather data), and Apple’s HomeKit to drive time and access:
If motion in the house/yard when Owners are away, turn the sprinklers on for X minutes
Line1: 3 minutes @ 4:00 am - M-Su
Line2: 10 minutes @ 4:05 am - M, W, F
Line3: 5 minutes @ 4:10 am - M,T,Th,Sa
Skip if rain within the last 24 hours > 0.1"
If today’s forecast temperature >90F and no rain, water all systems 4 minutes @ 5am