Spiders may remind you of Halloween fun, but that doesn't mean it's fun to share space with them in your home. Let's learn a few spider facts and find out how to keep them out of the house.
Meet the Spider
Spiders aren't insects. Insects possess six legs and three distinct body segments, while spiders have eight legs and two body segments. Even still, thanks to their small size and creepy-crawly vibe, we often think of them as bugs.
There are over 40,000 species of spiders worldwide, and over 3,000 species in North America alone. Baby spiders begin life as miniature versions of the adult spiders, then perform a series of molts as they grow to full size.
Why Spiders Are a Problem
Spiders tend to have a poor reputation. Whether it's because we dislike cobwebs, fear being bitten, or just think spiders look scary, humans tend to dislike spiders. But we often overlook their positive qualities. Most spiders are carnivores (some hunt, some trap with webs) and prey on various types of insects like flies and mosquitoes, so they're really quite helpful. Spiders generally try to avoid humans and rarely bite if left alone.1 Many spiders are far too small to bite humans even if they wanted to.
That said, some North American spiders can produce a painful bite, and a few species may cause serious health issues, including black widows, brown recluses, tarantulas, and hobos.
How Spiders Affect Your Pet
- Some pets may be more susceptible to spider bites than people. Unless the pet is actively provoking the spider, it's unlikely the spider will bite.
- If a pet eats a poisonous spider, it's possible the spider's venom could cause health issues.
How Spiders Affect Your Home
Even though spiders can be helpful, most people don't enjoy having spiders in the house.
- Unsightly cobwebs are probably the most visually obvious way that spiders affect your home. Dust-collecting cobwebs in the corners of ceilings or windows are definitely a nuisance and make your home look untidy.
- Cobwebs can also be a fire hazard.2
- Although many spiders are harmless to people, some spider bites can cause mild to serious health issues.
How Spiders Affect Your Yard
- Spiders may be attracted to areas of your garden or yard that feature places to hide, like mulch piles, garden debris, landscaping rocks or logs, and similar items. If you dislike spiders, you may not wish to provide this type of habitat as it might attract them to your yard.
- Because of their beneficial nature, you really shouldn't completely eliminate spiders outdoors.3 Spiders are predators that feed on annoying insects like mosquitoes, flies, earwigs, and cockroaches, so spiders can help to minimize those insect populations.
How to Get Rid of Spiders
- Prevent spiders in the house. It's challenging—and probably impossible—to block every entrance a spider could travel through. But keeping your home in good repair should go a long way towards keeping spiders out of the house. This includes making repairs to window screens and foundation cracks and crevices, and properly sealing around water pipes and electrical conduits.
- Use glue traps. Sticky traps designed for controlling cockroaches or similar pests can be effective on spiders as well. This is a very easy and inexpensive solution to incorporate.
- Vacuum egg sacs. Some spider species don't reproduce indoors, but some do. These species may use their silk to create web-like nests for their eggs. Vacuuming these egg sacs and the accompanying webs should help keep spider numbers down.
- Make your outdoor space undesirable. You can try to direct spiders away from your yard by eliminating locations where they might want to hide. At night, reduce outdoor lighting to avoid attracting insects, since spiders may follow their food source.
- Keep insects out of the house. Without insects to prey on, spiders won't be able to live indoors.4
- Try a spider spray. Some home insecticides like Adams Flea and Tick Carpet & Home Spray are also effective on spiders. A product like this or a general home spray like Adams Flea & Tick Home Spray can be used on various items and areas in your house to kill spiders.
- Use a yard spray. What kills spiders outdoors? An application of a yard spray can be used to create a spider "barrier" around the perimeter of your house to discourage spiders from coming inside.
Spiders may be helpful outdoors, but in your home is another issue entirely. The good news is that you can control spiders with a few simple steps.
1. Houseman, Richard M. University of Missouri Extension. "Spiders," March 2003. https://extension.missouri.edu/publications/g7386
2. Johnson, Steven B. and Dawna L. Cyr. University of Maine Cooperative Extension. "Electrical Fires: Prevention and Extinguishing," https://nasdonline.org/975/d000818/electrical-fires-prevention-and-extinguishing.html
3. Hahn, Jeffrey, Laura Jesse, Donald Lewis, and P.J. Liesch. University of Minnesota Extension. "Spiders," 2018. https://extension.umn.edu/insect-relatives/spiders
4. Bechinski, Edward John, Dennis J. Schotzko, and Craig R. Baird. University of Idaho Extension. "Homeowner Guide to Spiders Around the Home or Yard," January 2010. https://flathead.msuextension.org/documents/ag/spiders-insects/Idaho Hobo Spider bulletin.pdf