Acid PH (May 2006)

Geraniums: Acid pH in the growing medium can ruin your crop. This is what happens to leaves when pH of the growing medium starts dropping below 5.5. pH of the leach in this case was 4.9. Growers must monitor the pH on a regular basis not when symptoms appear. In this case grower has to apply potassium bicarbonate five times before pH rose to around 6.2. The damaged leaves have to be removed to sell these plants.

What happened with this geranium? It is not a pH issue. The plant entered into a flowering phase right after plug was transplanted into the container. How did it happen? Drying out was the main reason. The plants did not get water soon enough. What to do now: Remove flower, keep them well watered and well fertilized.