What leaf condition can indicate potassium deficiency besides yellowing?

Potassium deficiency in plants is often indicated by specific symptoms that reflect the plant's inability to properly manage water and nutrient transport. One of the primary symptoms is the presence of scorched tips and curling of the leaves. This condition arises because potassium plays a crucial role in the regulation of stomatal opening and closing, which affects the plant's ability to maintain water balance. When potassium is deficient, the plant can suffer from water stress, leading to the scorching of leaf tips and the curling of leaves as they react to this stress.

In contrast, bright green edges typically do not indicate a potassium deficiency; instead, they might suggest other nutrient imbalances or excesses. Dull color usually indicates a lack of vigor but is less specific than scorched tips for potassium deficiency. Dense foliage can be a sign of adequate health and nutrition; thus, it does not relate to potassium deficiency symptoms. Therefore, the identification of scorched tips and curling is a clear and direct indication of potassium deficiency in plants.