Glossary

Use this glossary of common hydroponic terms and get up to speed.

  • The condition of a sick plant with yellowing leaves due to inadequate formation of chlorophyll. Chlorosis is caused by a nutrient deficiency, usually iron or nitrogen; nutrient deficiencies are themselves often caused by a ph that is out of the acceptable range.

  • A plant produced through asexual reproduction including, but not limited to, cuttings, layering and tissue culture.

  • Misting plants with fertilizer solution, which is absorbed by the foliage.

  • A hydroponic system in which the medium, usually aggregate pebbles, is periodically flooded with nutrient solution and then drained again, feeding and aerating the medium and root system.

  • A very efficient watering system that employs a main hose with small water emitters. Water is metered out of the emitters, one drop at a time.

  • A hydroponic method wherein air pressure from a small air pump is used to percolate nutrient solution out through a ring of feeder tubing which encircles the plant.

  • The amount of dissolved solids, usually fertilizer salts, that are measured in water in parts per million.

  • Disease that attacks young seedlings and cuttings, causing stems to rot at the base; overwatering is the main cause of damping-off.

  • This micronutrient is an internal catalyst and acts as an electron carrier; it is also believed to play a role in nitrogen fixation.

  • To soak new Rockwool in an acidic solution to lower the ph from 8.0 to 5.5.

  • An acidic solution has a ph below 7.