The CWI container irrigation insert is a self-watering system designed to be dropped into most cylindrical and slightly tapered decorative pots. For over 30 years Tournesol’s proven vacuum-sensor watering system has precisely controlled moisture levels in the soil, watering the plant when the soil starts to dry. The oversize reservoir allows for refill intervals up to four times longer than typical hand watering (up to 2-4 weeks for interior plants, 1-2 weeks for exterior). This moisture control, when combined with sub-irrigation (watering from the bottom) makes the CWI the most water-efficient of all irrigation for pots & planters.