T E C H L I N E A S ™ D E S I G N G U I D E
NETAFIM @[email protected]
21/12/2009
31
DURATION OF IRRIGATION GUIDE:
Step 1
: Select Crop Factor (CF) & Evaporation Rates (ER).
From the tables below select the Crop Factor (CF) for the plant type that you are irrigating.
There are three levels of quality and appearance that can be achieved through irrigation.
Higher quality plant appearance can be achieved but has a higher water requirement. During
times of drought and water restrictions it might be better to aim for a Good to Reasonable
appearance.
The Evaporation Rate (ER) can be found by viewing the table below that has Average Mean
Daily Evaporation Rates for all major main-land capital cities in Australia. This data has been
collected from the Bureau of Meteorology from observations made over 2006 to 2007
averaging out daily evaporation rates.
To find current daily weather observations for the above and other cities visit the Bureau of
Meteorology website at
www.bom.gov.au/climate/dwo
.
Step 2
: Determine the daily Plant Water Requirement (PWR) by multiplying the plants Crop
Factor (CF) by the current Evaporation Rate (ER).
PWR = CF x ER
Step 3
: Determine the Weekly Water Requirement (WWR) by multiplying the daily Plant Water
Requirement (PWR) by seven (days).
WWR = PWR x 7
Step 4
: Determine the Total Water Requirement (TWR) by multiplying the Weekly Water
Requirement (WWR) by the Area (m
2
) that is being irrigated.
TWR = WWR x Area (m
2
)
