The answer to 'how long does spider treatment last' is that most spider treatments provide effective control for 2-4 months. The active ingredients in professional-grade spider sprays and dusts typically last 8-12 weeks before needing to be reapplied. However, factors like the type of spiders, the size of the infestation, and environmental conditions can affect the longevity of the treatment.
It's important to follow the product instructions carefully and reapply the treatment as directed, usually every 2-3 months, to maintain long-term control of spiders in and around your home. Regularly inspecting for new spider activity and webbing is also recommended to determine if additional treatments are needed.