What causes severed flower stems in plants?

Severed flower stems in plants are commonly caused by cutworms. These are larvae of various moth species that feed on the stems of young plants, often cutting them just above the soil line. Cutworms typically strike during the night when they are most active, making it difficult for gardeners to observe the damage until the next day. The damage is often evident as plants appear suddenly wilted or severed at the base.

Understanding the behavior of cutworms is crucial for effective pest management practices. Knowledge of their life cycle, feeding habits, and the timing of their activity can help in implementing strategies such as utilizing physical barriers, tilling the soil to expose larvae, or applying appropriate pesticide treatments to mitigate their impact on the plants.

The other options—fungal infections, beetle activity, and weather conditions—can lead to different types of plant stress or damage, but they do not specifically cause the characteristic severing of stems which is a distinct behavior associated with cutworms.