What is a common symptom of overwatering in ornamental plants?

Root rot is a common symptom of overwatering in ornamental plants because excessive moisture creates an unfavorable environment for roots. The roots require oxygen for respiration, and when they are submerged in waterlogged soil for extended periods, their ability to absorb nutrients and water diminishes. This anaerobic condition promotes the growth of pathogens that cause root rot, leading to the deterioration of the root system. Ultimately, this can result in the plant wilting, yellowing leaves, and even death, as the roots fail to supply the necessary support for the plant's overall health.

The other symptoms listed, while they may occur due to various stresses in plants, do not directly indicate overwatering in the same way that root rot does. Yellowing leaves and falling off can be attributed to multiple stress factors, including nutrient deficiencies or other diseases. Increased flower production is typically a result of optimal growing conditions and not associated with overwatering. Stunted growth can occur for various reasons as well, and while it may be a symptom related to root issues, root rot specifically encompasses the degradation of roots due to excess water. Thus, root rot clearly aligns with the symptomatology of overwatering in ornamental plants.