Utility of Rain Barrels for Irrigating Home Gardens
50 gallon drum used as storage cistern
evapotranspiration (ET) (loss of water from soil surface
through leaves) is .25 inches/day, if sunny day.
holding capacity of loam soils is 2 inches of water/foot
rooting depth of many garden plants = 1 foot
a plant management perspective, irrigation is best if no
more than 50% of water holding capacity is depleted. For
loam soil irrigate when 1 inch of ET.
in summer, if irrigating for plant management (not drought
management), irrigate every 4-5 days, adding one inch of
inch of water = .62 gallons over 1 square foot
gallons/.62 = 80.6 square feet of garden rooting area until
cistern is refilled.