Technical Bulletin Series
Support Info for the Garden Calculator Pro I
Irrigation "Interval" is the amount of time (in days or weeks) between one irrigation day and the next scheduled day.
Interval versus Times per day: If the irrigation schedule is set to water 2 times on Monday, Thursday and Saturday, the "Interval" is three days a week. Even if it is to water only one time on Monday, Thursday and Saturdey - the Interval is three days a week.
Multiple waterings in a single day simply allows more time for the moisture applied to soak into the soil, and has a much different impact on soil moisture than the number of days between watering has.
Days bewtween irrigations provides the time necessary for evaporation and transpiration (plant water consumption) to allow air into the soil, so the plant can respire (or breathe). If the soil is not given enough time to adequately dry during the irrigation interval, the root system will suffocate, causing the roots to be unable to absorb moisture.
Pre-Existing Moisture is the amount of soil moisture remaining following the irrigation interval, and before the next irrigation begins. The warmer the temperature the less soil moisture will remain, so Interval must be adjusted seasonally.
Adequate and appropriate irrigation interval is vital for plant health. The Garden Calculator Pro-I provides both the amount of water to apply during a watering day, AND the proper irrigation interval to allow for adequate drying before re-applying water again.