Yellowing leaves can be a symptom of several maladies. Overwatering is the most common, followed by the early stages of disease. Or it could be that the soil pH is out of whack. Roses like a slightly acidic soil. A soil that is too alkaline or deficient in iron may cause general yellowing. If you've ruled out overwatering and diseases, the problem is probably due a nutritional problem. Hope this helps you determine just why the leaves are yellow. |