pH is a measure of the acidity or alkalinity of a solution. Values below 7 are acidic, and above 7 are alkaline. The acidity / alkalinity scale affects all kinds of daily situations: athletes know that sports drinks are acidic for fast absorption. Foodies know the sour taste of grapefruit, yogurt, kombucha and pickles is the result of high acidity in these products. Acidity has played a primary role in the preservation of fermented foods for centuries. On the other end of the scale, high alkaline water causes lime build-up in coffee machines or settles an upset stomach.
Gardeners know that changing the pH level of soil changes the color of hydrangeas from pink to blue. The overall importance of pH levels in both soil and water cannot be understated concerning the availability (or lack of) both macro and micro nutrients.
The best pH level for flower solutions is between 3.5—5.0. Lowering the pH boosts uptake, dissolves air bubbles blocking flow and makes the pollution-busting ingredients perform at 100%.
Measuring when mixing matters
Taking the pH measurement is a quick snap shot of correct mixing. Dip a pH strip into the vase or bucket and match it with color scale on the package. If the pH is above 5, the solution is incorrectly dosed. If pH measures 7 or above, it’s just plain tap water. If pH is below 3, stem damage and/or foliage burn can occur.
Finally, avoid using acidic solutions (e.g. hydration and flower foods) in metal containers or lead crystal vases. Metal contains are a problem because the exchange of metal ions can be toxic to flowers at very low levels, especially chlorine, boron, zinc, copper and iron. Leaf tip burn, dark petal tips and leaf yellowing can result. Lead crystal is a problem because it becomes porous with age and is easily etched when in contact with acidic solutions.
About Gay Smith
Gay’s career has been entirely focused on flowers. Working in California, Holland and Miami has provided first-hand experiences with the challenges growers face, the nutty habits of wholesalers, hectic systems of bouquet makers and funky practices of retailers. For the last 16 years, she’s worked as the technical manager for Chrysal, working to advise and advance quality practices.