Garden & Greenhouse April 2018 Issue | Page 39

solution should feel sort of “silky” and tepid—neither warm nor cold. Andrew Taylor is the Chief Chemist at FloraMax. You can visit their website at Floramax.com. Water Thoroughly When hand watering or top feeding, do so slowly, evenly and gradually. Aim for around twenty percent of the nutrient solution to run out of the bot- tom of the pots. Run-off helps to keep the root zone cleaner with less salt build-up. Dry Patches from Automated Top-Feeding Water the surface of the medium at as many points as possible otherwise areas of the root-zone will risk being left un-watered.  Devices such as water-rings or spray nozzles are a good alternative to single point drippers. Check Run-Off For run-to-waste coco coir or soil systems, pe- riodically collect some of the run-off and check its EC. If it measures more than 0.5mS (500 µS or cF 5.0) above the EC of the input nutrient solution then consider fl ushing through with a milder solution (or even pure water) to help clear the root zone of ex- cess salts. For example, if the nutrient solution has EC 1.7mS but your run-off measures 2.3mS (or more) then it is time to fl ush. Hard Water Problems Hard water is typically alkaline—and so are many nutrient additives. “Alkalinity” is what typically drives nutrient pH above and beyond 6.5. This is the point at which many trace elements (e.g. iron) begin to de- stabilize. GG April 2018 www.GardenandGreenhouse.net 39