Florida Waterwise Landscapes - Alliance for Water Efficiency

5. Irrigate Efficiently
The major oasis area in most yards is the grass.
In some Florida locations, rainfall may be adequate
for turf, but some supplemental water may
be required.
If an irrigation system is needed, manual
methods may be the most thrifty. If the landscape is
planted with species suited to existing conditions,
little or no irrigation will be needed once the
landscape is established, so an automatic system isn’t
necessary. For occasional, manual irrigation of grass
areas, a rain gauge is a valuable tool. It can tell you
how much rain has occurred and can be used to
measure the needed 1/2 to 3/4 inch recommended
for grass areas.
Inground irrigation systems are convenient, but
often waste water. While the goal of these systems is
to uniformly and efficiently irrigate lawns, some may
be used to overwater.
Florida law requires an automatic rain sensor
shut-off device that is properly installed and
functioning on all automatic irrigation systems
installed after May 1, 1991 (section 373.62, FS). The
rain sensor overrides the irrigation system settings
when there has been sufficient rain. Some local laws
also require older systems to be retrofitted with
shut-off switches.
In addition to having a properly functioning
irrigation system, the system’s efficiency will depend
on you having the correct spray-head types for the
various zones to be irrigated and how your landscape
has been planted.
For example, turf areas and planting beds should
be separated into different irrigation zones because
they have different moisture needs.
Select the emitter head that will deliver water to
the plant roots as efficiently as possible. For planting
beds, microirrigation system emitters deliver water
directly to the plant. Microirrigation types include
“drip,” “trickle,” “microsprays” and “bubblers.”
Microsprays or microjets are often used in
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shrubbery or on groundcovers. Bubblers are
normally used on trees or large shrubs.
Within a zone, all the heads should have the same
precipitation rate — the rate at which an irrigation
head delivers water — in order to have even
distribution within the zone.
Microirrigation delivers water at rates of 60
gallons per hour (gph) or less. Usually, bubblers emit
1 gph and a single-drip emitter, 2 gph. For drip line,
45 gph per foot of line is delivered and up to 60 gph
for microsprays. High volume heads are rated at
60 gph or more.
Irrigation System Installation
If installing an
inground automatic
irrigation system,
follow these guidelines
to optimize the
system’s efficiency:
1. Properly install automatic rain sensor shut-off
device and check regularly to ensure it is
functioning properly.
2. Install a back-flow valve.
3. Separate zones for turf and non-turf areas.
4. Match precipitation rates on all heads within
a zone (e.g., rotors and spray heads on
separate zones).
5. Choose each device based on what will most
efficiently water each group of plants.
6. Use pressure-regulated valve heads.
7. Use rotors in turf areas, spaced for
“head-to-head” coverage.
8. Check valves on rotors and sprays in
low-lying areas.
9. Verify that the system design meets state
specifications for landscape irrigation installation
as found in Florida Building Code, Appendix F.
10. Schedule appropriate irrigation that supplements
rainfall to no more than 1.5 inches of water per
week for turf areas, and less in planting beds, in
the spring. Water less during the other seasons.
11. Conduct regular inspection and maintenance to
detect leaks, clean filters and realign or replace
rotors and spray heads, as needed.