Depending on the size of your project, control systems can be simple & low-cost, through to multi-zone options for larger areas.
Battery-powered timers, (examples shown here) for connection to taps are particularly useful for D.I.Y. schemes in the garden. Like the heating controls of your house, they are simple to program. If you need to fill a bucket, disconnect the hose and turn the water on with the "button" rather than at the tap! Good quality alkaline batteries will usually give a seasons operation. Timers do restrict the flow a little, so they should only be used where the downstream zone does not contain more than 200metres of Leaky Pipe LP12H.
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On a more costly level, for systems in landscaping that do not have the facility for laying control cabling-ie roundabouts & remote areas. A battery-powered programmable solenoid valve can be plumbed discreetly into the water supply pipe. The hand-held programmer shown here is carried from valve to valve & connected to the valve to set its watering schedule. Once programmed, the valve can be closed into a valve box, out of sight, away from harm. (Communication-by-radio versions are also available).

The larger irrigation systems will invariably use a central irrigation controller that has to be connected to a solenoid valve or valves that will control the flow of water to the zone or zones. Zone watering is done sequentially to whatever is set in the controller. The solenoid valves may be positioned close to the controller with pipes taking the water to each zone. But for extensive systems, the valves will be remotely positioned within the zone.

The planning and design of such systems is usually a specialist job, so it is best to ask a good company about this option. Maybe contact us through info@leakypipe.co.uk
Mains-powered, multi-zone irrigation controllers.
On the left, a wall-mounted, complete assembly.