Certified Professional Horticulturist (CPH) Practice Exam

What is a common sign of overwatering in indoor plants?

1. New leaf growth

2. Leaf yellowing and drooping

3. Flower droop

4. Increased pest presence

The correct answer is: Leaf yellowing and drooping

Leaf yellowing and drooping is a common sign of overwatering in indoor plants. This occurs because excess water saturates the soil, leading to poor aeration and root oxygen deprivation. When the roots struggle to absorb oxygen, they can become damaged, which in turn affects the plant’s ability to take up nutrients and water effectively. As a result, the leaves may turn yellow (a symptom of nutrient deficiency) and droop due to the plant experiencing stress from its roots being constantly waterlogged. In contrast, new leaf growth typically indicates healthy growth conditions and is not linked to overwatering. Flower droop can arise from various factors including age or stress but is not a specific indicator of overwatering. Increased pest presence can be a response to environmental stress but is not directly tied to the act of overwatering itself. Understanding these signs helps in maintaining healthy indoor plants by allowing the owner to adjust watering practices accordingly.