Properly designed and programmed,
automatic irrigation systems can save you time and money.
Choose a system that can be reprogrammed easily to adjust
to changing seasonal requirements.
Most systems use a system of underground
pipes, sprinklers, and emitters to water specific areas
of a garden or turf, and divide the property into specific
areas so that plants with similar root depths and watering
needs can be watered by the same irrigation valve and cycle.
An irrigation controller includes a timer that activates
the valves for each watering zone. The timer allows you
to water at the most efficient time of the day - usually
the very early morning hours - when evaporation losses are
minimal.
Systems provide two categories
of irrigation: overhead and low volume/drip.
Overhead systems
use sprinkler heads to spray water over an area. In arid
and semi-arid areas, these are recommended primarily for
turf irrigation. Efficient
techniques for watering lawns are discussed elsewhere
on this website. Overhead systems may use up to five gallons
of water per minute, and apply up to 1½ inches of water
per hour. System efficiency is dependent on water pressure
and availability, as well as environmental factors such
as watering when winds are minimal, and on maintenance factors,
such as seeing that sprinkler heads are correctly aligned
and unclogged.
Drip irrigation
emits a slow and steady application of water at the roots
of plants and shrubs, directly where it is needed rather
than through the air where it evaporates. The rate of flow
is determined by the size of the aperture of the emitter
and by the number of emitters programmed on a single valve
or cycle. Care should be taken to not overload the system
and exceed the household's water pressure capacity. It is
generally preferable to program several areas with separate
watering cycles than try to water a large area on a single
cycle.
If you are determined to install
an irrigation system yourself, seek advice from a reputable
retailer or from your local Cooperative Extension office.