The second option involves injecting potassium bicarbonate into the irrigation water. Continued use of this method may require a grower to switch to a lower potassium source fertilizer. In those cases, growers typically choose to install an acid injector. Others methods are selected if individual blocks of plants require a lower media pH. Materials such as elemental sulfur, ammonium sulfate and ferrous sulfate have all been used. Caution must be used when considering using ammonium sulfate and ferrous sulfate as you need to account for the nitrogen and iron that accompanies these materials.
Growers can also affect media pH by selecting specific forms of nitrogen.
The use of high ammoniacal-nitrogen based fertilizers can lower the media pH over time. Rate recommendations take into consideration the change in pH and type of media and may be obtained from grower manuals or your Cooperative Extension Service. EC does not provide details on the type or amount of individual salts present. High ECs can contribute to poor shoot and root growth. The first objective is to determine the source for the elevated salts.