This system easily pays for itself in areas of expensive water.
WaterGreat SR-1 12 Plant Kit:
An inexpensive, very easy to use, self-contained, solar powered watering system based on auto timing and WaterGreat's soil or ground moisture sensor (probe) – designed for years of use in water pressure systems. Instead Select Gravity Feed System or Gravity Valve and Controller Only
These 'all in one' watering systems are ideal for those wishing to get a system that will work well for them. Many people do not know where to start with an automatic watering system, especially a cutting edge product. These systems use automatic drip irrigation methods with the flow based on the number of plants and the kit chosen. Select the complete kit (and add on) based on the number of plants you need to water. The base unit includes 6 pressure compensating outputs. The retrofit connects directly to the basic system if you need more.