At what growth stage should bindweed and perennial pepperweed be sprayed?

Spraying bindweed and perennial pepperweed during their early flowering stage is optimal for effective control. At this point in their growth cycle, the plants are actively allocating resources to reproductive structures, which makes them more susceptible to herbicides. The chemicals can be absorbed more efficiently and translocated throughout the plant, targeting not just the foliage but also the roots, which is crucial for perennial weeds that often regenerate from root systems.

Targeting these plants during their early flowering stage often helps to mitigate the risk of seed production and spread, further aiding in long-term management efforts. Treating weeds at this stage can significantly reduce their population before they set more seeds, contributing to effective control in future seasons.

In contrast, spraying during the seedling phase or immediately after germination may not be as effective, as the plants are not yet established enough for the herbicides to have a lasting impact. Spraying in late fall after leaves drop can lead to reduced efficacy because the plants are entering dormancy, which hinders the uptake of herbicides.