TESTED FOR YEARS With CANNA HYDRO nutrition for fast growing plants, CANNA became a pioneer in the cultivation on substrates. With substrate cultivation, the soil is replaced by an inert growth medium. Inert growth mediums, such as rockwool, do not contain any nutrients. HYDRO is the best nutrition for growing on inert substrates. CANNA HYDRO is used especially on ‘run-to-waste’ systems; these are systems where the drain water is drained off or so called open-hydroponics systems. CANNA HYDRO has been the most used nutrient in the Netherlands for years.