User's Manual

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Appendix C: Watering Guidelines Setting the Irrigation Controller for UgMO
Setting the Irrigation Controller for UgMO
Ideally, the best irrigation program is one that has available
water in the soil for plant uptake for the longest period of time.
Lighter, more porous soils like sands saturate quickly but drain
just as quickly in many cases. Heavier, less porous soils like
clays and organic soils saturate more slowly but also hold on
to the water for much longer periods of time. Therefore, no one
watering cycle and duration is ideal for all soils. However, two
watering cycles a day will always be more efficient for prolong-
ing availability of water than one cycle will.
Sandy Soil Types:
A single irrigation cycle will saturate the soil fairly quickly. Any
extension of time only prolongs the availability of water due to
the longer duration of water input. Whether the water stops
after 20 minutes or 60 minutes, the dry down is very much the
same. So the availability of water ends shortly after the cycle
ends. This is assuming that the water drains well beneath the
root zone. Things that prevent this are layers and other hinder-
ing changes like overlapping soil types, but even in these situa-
tions, two cycles better than a single cycle.
Loam, Clay and High Organic Soil Types:
These soils accept water much better when they are wet well
into the depth of the soil. However, one long cycle will run off of
the surface before it saturates through the soil since the input
(precipitation rate of the system) exceeds the infiltration and
percolation rate (movement of water into and through the soil).
So a dual daily cycle would help this soil by allowing a certain
amount of water to trickle through the soil and allow that soil
to accept more water even more deeply into the soil.
Ideal Watering Cycles for Use with UgMO:
Determine the typical run times for a given zone for the hot-
test period of the year. For example, if a zone is typically set
to run for 60 minutes during August. UgMO will ensure that
the zone is not overwatered during other times of the year.
Program each zone on the irrigation clock for two cycles, 4-6
hours apart by dividing the original one cycle duration in half.
So a 60 minute cycle now becomes two (2) 30 minute cycles 4-6
hours apart.