Written collaboratively by Patrick Wagner, Adam Varenhorst, Amanda Bachmann, Philip Rozeboom, and Bradley McManus.
Have you noticed an increase in the number of spiders showing up around your home lately? If the answer is “yes,” then you are not alone. During fall, spiders and many other creepy crawlers try to find safe places to escape the cooler weather (Figure 1). Unsurprisingly, a warm cozy home is often high on their list of choices. There are some simple steps you can take to help prevent spiders, and other arthropods, from invading your home this fall.
Sanitation and Prevention
First off, make sure that your home is sealed up tight. Caulking around gaps in door and window frames (especially ground-level windows) can help eliminate points of entry for would-be invaders. Check for cracks and fill any gaps around the foundation as well. If you have lots of windows, it is a good idea to check the screens for damage (Figure 2). If you find screens with holes in them, see if you can get them patched or replaced.
Keep things clean and maintained around the outside of your home. In the fall, leaf litter and other debris tends to collect in gutters and around the foundation. This buildup should be removed because it provides shelter for spiders until they find an opportunity to get indoors. Make sure to also cut back any overgrown shrubs or trees near your home, since branches touching the house can act as a bridge for spiders and other arthropods to gain entry. Always avoid stacking firewood up against exterior walls. It is recommended to keep firewood piles several feet away from structures and in an elevated location.
Sweep, dust, and vacuum on a regular basis to remove and deter any new arrivals. It is important to especially clean inside closets, in dark corners, and underneath furniture. Not only try to keep your home clean but also free of clutter. Spiders like to hide under or behind just about any object indoors. Minimizing the amount of clutter helps reduce the number of hiding places while also making cleaning much easier.
Perimeter Sprays
Insecticide perimeter sprays can be used if none of the previously listed tactics prove effective. These special formulations are designed to be applied around the exterior foundation of buildings and around doors and window frames. Some products are labeled for indoor use as well and can be sprayed around baseboards and in those hard-to-reach cracks and crevices. Most perimeter sprays containing active ingredients such as Bifenthrin have residual activity of up to 3 months and can provide lasting protection throughout the fall season. However, reapplication may be necessary depending on which product you choose. When handling any insecticide, always remember to read and follow the label instructions to ensure safe and proper usage.
