Pest Control for Black Widows: How To Get Rid of Black Widow Spiders (Signs)

Georgette Kilgore headshot, wearing 8 Billion Trees shirt with forest in the background.Written by Georgette Kilgore

Pest Control | April 2, 2024

Person watches exterminator deploy pest control for black widows, showing how to get rid of black widow spiders safely, and when to call an exterminator for black widows, prevention tips.

Pest control for Black Widows is an important process for keeping these venomous spiders out of your home and yard.

Black Widow spiders are infamous for their shiny black bodies, red hourglass markings, and venomous bite.

While they are not aggressive, Black Widows can deliver a potent neurotoxic venom if threatened, making them a concerning pest to find around homes.

Additionally, while Black Widow bites are rarely fatal, their neurotoxic venom can cause severe pain, muscle spasms, nausea, and other unpleasant symptoms.1

To protect your home and avoid the risks of a bite, getting rid of Black Widow spiders through proper methods is essential.

In this comprehensive Black Widows pest control guide, you will learn how to identify Black Widows, signs of a Black Widows infestation, and effective control techniques to get rid of Black Widows using both chemical and natural methods.

With vigilance and preventative pest control for Black Widows, you can keep these venomous spiders away from your property.

Pest Control for Black Widows: How To Get Rid of Black Widows Safely

Pest control for Black Widows ultimately relies on a combination of preventative and direct measures.2

Here are the best ways to safely eliminate Black Widows from your home and prevent future infestations:

7 Natural Methods of Getting Rid of Black Widows

For non-chemical pest control alternatives, these natural methods can help remove or deter Black Widows:

  1. Strong scents: Essential oils like peppermint,7 eucalyptus, tea tree, and citrus repel spiders when applied in dark, infested areas.
  2. Chestnuts: The organic compounds contained in chestnuts reportedly deter spiders.8 Place chestnuts in corners and entry points.
  3. Bird nest boxes: Attract insect-eating birds like wrens to prey on Black Widows around your home.
  4. Diatomaceous earth: The sharp fragments in diatomaceous earth physically damage the spiders’ bodies and exoskeleton when applied in infested areas.9
  5. Vinegar: The acetic acid in vinegar is deadly to spiders. A vinegar-water solution sprayed directly on Black Widows will kill them.
  6. Sticky traps: Traps with heavy-duty adhesives can immobilize spiders when strategically placed near webs or nesting sites.
  7. Vacuuming: Carefully vacuuming webs, egg sacs, and spiders can provide control when performed vigilantly.

For severe infestations outdoors, contacting a pest control professional is advised since there is no guarantee of completely eliminating or deterring Black Widows with natural methods alone.

How To Get Rid of Black Widows With Pesticides

For more potent chemical control indoors and outside, pesticides specifically labeled for Black Widow spiders are highly effective:

  • Pyrethroid sprays: These common pesticides are derived from chrysanthemum flowers. Active ingredients like permethrin, bifenthrin, cypermethrin, and deltamethrin kill Black Widows on contact.6
    Apply crack and crevice treatments where spiders may hide and nest.
  • Residual sprays: Products containing pesticides like lambda-cyhalothrin, cyfluthrin, and tetramethrin provide lasting residual activity killing spiders for weeks after application.6 Use along the building perimeter or foundation.
  • Dust: Formulations of pyrethroid or diatomaceous earth dust applied into voids, cracks, and secluded areas can kill spiders who come into contact. The sharp particles also abrade their exoskeleton.
  • Aerosol sprays: Fogger cans or spider spray containing pyrethrins create a fine mist that can penetrate cracks and instantly kill spiders on contact.5 Look for cans with an attached straw for pinpoint application.

For best results, combine spraying and localized dust treatments. Additionally, be sure to consult pest control pros for whole-home treatments if infestations are severe.

Graphic illustrating the distinguishing characteristics of male and female black widow spiders, including differences in size, color, and markings.

Always carefully follow label directions when applying any pesticide.

Pest Control for Black Widows: What Is the Best Black Widow Spider Killer?

Getting rid of Black Widow spiders relies on a combination of preventative and direct measures.2 Insecticide sprays, dusts, and concentrates containing deltamethrin, cyfluthrin, bifenthrin, or permethrin provide optimal spider control.

Directly apply to spiders and webs. Treat a perimeter band around foundations.

Dust voids and potential entry areas. Traps and vacuums also help remove spiders.

How To Get Rid of Black Widows in the House

Getting rid of Black Widows that have made their way indoors involves inspecting, cleaning, and pest-proofing your home:10

  • Carefully check likely nesting sites in garages, sheds, basements, crawl spaces, attics, and cluttered storage areas for spiders, webs, and egg sacs. Use glue boards and sticky traps to capture spiders you find.
  • Vacuum any webs, spiders, and eggs thoroughly. Make sure to seal and securely dispose of the vacuum bag afterward.
    Steam cleaning is also effective for pest removal.
  • Clean floors and storage areas to remove food sources like crumbs and insect prey that attracted Black Widows inside
  • Caulk cracks in your home’s foundation and seal entry points around pipes and vents with copper mesh, weatherstripping, or screen. Repair torn window screens as well.
  • Apply pyrethroid sprays or dust into cracks, corners, under appliances, around pipe openings, and other voids where spiders may hide
  • Keep plants trimmed back from exterior walls and doors. Move woodpiles and debris far from the foundation to discourage Black Widows near entry points.
  • Inspect everything thoroughly before bringing items indoors including boxes, plants, firewood, grocery bags, and even shoes left outside. Spiders often hitch rides inside.

With vigilance and sealing up access, Black Widows can be effectively excluded from your home. Call on professional pest control if infestations persist.

How To Get Rid of Black Widows in the Yard

Outside, Black Widow spiders reside in areas like wood or rock piles,1 vegetation debris, tree stumps, and rodent burrows.

Focused view of a black widow spider with a red marking on its abdomen poised on a delicate web.

Here are some ways to get rid of and discourage outdoor Black Widows:

1. Remove Woodpiles and Debris

Eliminate places for Black Widows to build their tangled webs outdoors.

  • Break apart and dispose of wood piles and lumber far from your home
  • Clear out yard debris like piles of sticks or brush. Black Widows tend to nest underneath.
  • Keep grass cut short and trim vegetation back from the foundation. Remove heavy mulch near walls.
  • Store pallets neatly and elevate them off the ground. Routinely check for spiders
  • Install motion-sensor security lights on porches, sheds, or garages since Black Widows avoid bright lights

2. Apply Pesticide Around the Exterior

Treat the perimeter of sheds, garages, and your home’s foundation to prevent outdoor spiders from entering.

  • Focus on applying pesticides around potential entry points like crawl space vents, weep holes, doors, and windows
  • Products containing pyrethroids work well for exterior spider treatments

3. Remove Their Food Source

Many insects that Black Widows prey on are attracted to exterior lights and standing water. Therefore:

  • Install yellow or sodium vapor light bulbs around your home. Avoid bright white bulbs that draw lots of bugs.
  • Fix leaky outdoor faucets and dry up standing water. Eliminate mosquito breeding sites
  • Seal trash cans and keep pet food indoors so it does not attract ants, flies, roaches, and other spider prey

4. Encourage Natural Predators

Certain animals feed on Black Widow spiders.5 Invite them to your yard:

  • Install birdhouses and nesting boxes for insect-eating birds like chickadees, wrens, or bluebirds
  • Build bat boxes since bats also consume substantial insect prey
  • Avoid killing non-venomous spiders like wolf spiders that compete with Black Widows

With proactive and preventative pest control, you can successfully evict Black Widows from establishing webs and egg sacs around the exterior of your home.

What Are Black Widow Spiders?

Black Widow spiders belong to the Latrodectus genus and there are several species found throughout the United States.5 The most common is the Western Black Widow (Latrodectus hesperus) commonly found west of the Mississippi.3

A black widow spider, marked with vibrant red spots, hangs delicately in a black widow web.

(Image: Alfried H., Germany16)

The Southern Black Widow (Latrodectus mactans) occurs in southeastern states.4

Black Widow

(Latrodectus)

Black Widow spider in an oval frame on a green background.
  • Description: Fully grown female widow spiders often exhibit a glossy black or deep brown hue, adorned by a unique hourglass design in red or orange on their lower abdomen, though variations include some with red dots or without any distinct markings. Males and the younger spiders generally have a range of red or white stripes, bars, or dots on the top side of their abdomen.
  • Natural Habitat: Low shrubs, dark and undisturbed areas
  • Locations: Southern region of the United States

Image Credit: jgiammatteo17

How To Identify Black Widow Spiders

Accurately identifying Black Widow spiders is the first step in proper pest control.5

Adult female Black Widow spiders have a distinctive appearance with shiny jet-black bodies and a reddish hourglass shape on the underside of their large, rounded abdomens. They measure about 1.5 inches (38 mm) long when their legs are extended.

Male Black Widows are smaller, around 0.5 to 0.75 inches, with varying amounts of red, white, and black markings on their backs and legs. Unlike the female, males lack an hourglass and are not considered dangerous to humans.6

Black Widows are nocturnal spiders that construct irregular, tangled webs, often close to the ground and rarely leave the web. They prefer protected locations like piles of debris, wall voids, corners of unused sheds and outbuildings, undersides of outdoor furniture, openings in hollow logs, and rodent burrows.

A black widow spider, identifiable by its dark color, on a textured white surface.

(Image: AngeliasAtelier15)

Indoors, they may take up residence in cluttered garages, crawl spaces, storage rooms, or basements. Black Widows often reside upside down in the center of the web.

Identifying egg sacs can also indicate Black Widow activity. The round, papery, off-white egg sacs are about 1/2 inch wide.

Each contains hundreds of eggs that hatch into spiderlings. The presence of multiple sacs indicates a well-established Black Widow population.

Being able to identify Black Widows and their habitats allows you to target treatment correctly and avoid accidentally harming beneficial spiders.

Signs of a Black Widow Spider Infestation

If Black Widows take up residence in or around your home, they can pose serious health risks. Watch for these common signs that Black Widow spiders may have invaded your property:5

  • Multiple black spiders with distinctive red hourglass marking
  • Strong, messy webs in garages, basements, sheds, or under patio furniture
  • White, tan, or gray egg sacs in corners of webs containing hundreds of spiderlings
  • Insects caught in webs: Black Widows prey on flies, ants, cockroaches, earwigs, etc.
  • Pairs of fang marks on captured prey: Black Widows use venom to immobilize insects
  • Increased number of spider bites on pets or humans

An infestation can multiply rapidly since female Black Widows produce several egg sacs, each containing hundreds of spiderlings. Therefore, act quickly at the first signs of Black Widows setting up webs on the premises.

When To Call a Professional Exterminator for Black Widows

While DIY pest control can be effective for minor Black Widow issues, contacting a licensed pest management professional is advisable in these situations:

  • Severe Infestations: If Black Widows are prevalent in or around the home despite your efforts it might be time to seek professional help. Seeing multiple spiders, webs, and egg sacs indicates a heavy infestation.11
    Professionals have the proper training, equipment, and stronger pesticides to fully eliminate large populations.
  • Health and Safety Risks: If you have small children at home or family members with sensitivities, the dangers of venomous spiders may warrant professional help.11 Trained exterminators can treat infestations safely and effectively while eliminating risks to your family.
  • Difficult-to-Access Areas: Exterior facades, rooflines, trees, and high interior spaces are challenging for DIYers to fully treat. Professionals can access these areas and completely eradicate infestations.
  • Time and Labor: For busy homeowners, calling pest control to handle the intensive process of inspection, web, and egg sac removal, applying pesticides, and exclusion is often preferable despite the cost. Professionals can also advise on future prevention.

Why It’s Important To Call a Professional Pest Control Company

There are several benefits of hiring a professional pest control company versus tackling a Black Widow infestation yourself:

  • Customized comprehensive treatment plans: Licensed technicians will inspect your property, identify problem areas, and devise a treatment plan specific to your situation and infestation levels. They will use a combination of tactics including trapping, exclusion, pesticides, and habitat modification for complete Black Widow removal.
  • Effective pesticides: Professionals have access to more potent, restricted-use chemicals and precision equipment for effectively eliminating Black Widow populations. The stronger pesticides fully kill spiders and provide residual activity.
  • Training and expertise: Exterminators possess extensive knowledge of spider biology and behavior.12 Their hands-on training and experience enable them to find nesting areas customers may overlook.
    Their expertise results in a more thorough elimination of Black Widows.
  • Monitoring services: A reputable pest company will return and re-treat if any Black Widows return after their service.12 They also provide preventative treatments.
  • Safety and compliance: Licensed technicians are educated on the safe use of pesticides and proper protocols for applications in homes with children or pets present.12 They follow all regulations for the chemicals used.
  • Warranties and insurance: Professional pest companies often provide service guarantees and satisfaction warranties. They also carry liability insurance protecting customers if any incidents occur.

Choosing the Right Pest Control Service for Black Widows

Follow these tips when selecting a pest control provider for treating Black Widows:2

  • Look for current licenses: Verify state licensing for the pest control company and the individual field technicians. This ensures proper training and continuing education.
  • Check for liability insurance: Reputable companies carry insurance protecting you from liability for technician actions, spills, or other incidents during service.
  • Read online reviews: Research companies online and read customer reviews on online Yellow Pages to gauge their reputation and service quality specifically for spider treatments.
  • Ask about their Black Widow expertise: Inquire about specific training and tools for treating Black Widow infestations. Ask about their elimination strategy and the pesticides used.
  • Request an inspection: Many companies offer free inspections to assess your situation firsthand before providing a quote and treatment recommendations.
  • Compare multiple quotes: Get bids from at least 3 pest control providers to compare costs and services. Beware of lowest-cost providers who may cut corners.
  • Read all contracts thoroughly: Make sure you fully understand the extent of services, coverage, warranties, follow-up, and costs before signing a contract.

For severe or recurring Black Widow problems, don’t hesitate to call in a pest control professional. With their expertise, equipment, and stronger pesticides, professionals can provide a safe and effective solution.

Prevention Tips and Ongoing Measures: How To Keep Black Widows Away

Consistency is key for preventing Black Widows from returning and gaining a foothold.6 Implement these tips to help deter Black Widow spiders from your home and yard:

  • Remove trash, yard debris, and clutter to eliminate protective hiding spots for Black Widows
  • Seal cracks, holes, and crevices with caulk or concrete to prevent access. Cover vents and drains with fine mesh.
  • Trim back vegetation and branches touching exterior walls, fences, or your home’s foundation
  • Install bright lighting around entry points and doorways. Black Widows avoid illuminated areas.
  • Apply sticky barriers like Tanglefoot around foundation walls and potential entry points to trap wandering spiders
  • Spray concentrated essential oils or vinegar water solutions around windows, doors, and the building perimeter to deter spiders
  • Use insecticides like pyrethroid sprays or dust in an annual preventative treatment around the property perimeter and home exterior.
  • Consider installing screening or sheeting on deck and patio crawl space openings. Check for and seal any gaps around the barriers.
  • Inspect plants, firewood, and items before bringing them indoors to avoid “hitchhiker” spiders entering your home

With vigilant pest control for Black Widows and diligent prevention measures, you can deter these venomous spiders from invading your indoor and outdoor living areas.

What To Do After a Black Widow Bite

Though rare, Black Widow bites do occur when spiders get trapped against human skin or when defending egg sacs.

A black widow spider, with red marking on its abdomen, clings to its web, closely guarding a pale yellow black widow egg sac.

(Image: Tyler C.14)

Here is what you should do following a bite:1

  1. Wash the bite area thoroughly with soap and cool water. Apply an antiseptic cream.
  2. Apply an ice pack wrapped in cloth to the bite site to reduce swelling and pain. Keep the bite elevated.
  3. Note any symptoms like acute pain, rigid abdominal muscles, nausea, sweating, or muscle spasms. Severe reactions warrant immediate medical care.
  4. Take an over-the-counter pain medication like acetaminophen (Tylenol) or ibuprofen (Advil) as directed.
  5. Monitor bite symptoms closely for the next 8 to 12 hours. Redness, swelling, and pain may persist and intensify.
  6. Seek evaluation at an urgent care clinic or emergency room if nausea, difficulty breathing, chest pain, seizures, or other concerning symptoms develop after a bite.
  7. Follow up with your physician after a Black Widow bite. Additional treatment may be warranted based on your reaction.

Though Black Widow antivenom exists, it is rarely administered.13 Doctors more commonly prescribed muscle relaxers, pain relievers, and benzodiazepines to manage bite symptoms.

Most bites resolve within a few days with proper first aid and monitoring.

Effective pest control for Black Widows relies on properly identifying them, inspecting for signs of infestations, directly treating spider nesting sites, and proactive prevention. By understanding Black Widow habits and vulnerabilities, you can implement a strategic approach to get rid of Black Widows around your home using the techniques outlined here.

By employing careful strategies, maintaining vigilance, and applying consistent efforts, you can effectively manage pest control for black widows, ensuring these hazardous spiders are eradicated from your property permanently.

Frequently Asked Questions About Pest Control for Black Widows

Can Black Widow Spiders Come Back After Treatment?

If preventive actions lapse, Black Widows may reappear and re-establish themselves after initial treatment due to their ability to enter through tiny cracks. Keep sealing entry points, cleaning up clutter, trimming vegetation back from your home’s exterior walls, and remain alert to signs of returning spiders.

Can I Get Rid of Black Widows Myself?

Yes, it is possible to control minor Black Widow issues yourself using pesticides, traps, vacuum removal, exclusion techniques, and diligence in monitoring and cleaning up potential nesting sites. However, if you have a major infestation, live with children/pets, or feel uncomfortable dealing with venomous spiders, it is best to hire a professional pest control company for Black Widow removal services.

How Dangerous Are Black Widow Spiders?

Black Widow spiders are highly venomous but their bites rarely cause death. Additionally, only the female Black Widow’s bite is dangerous. Bites typically cause symptoms like mild to moderate pain, muscle cramps, nausea, and weakness, and it’s important to seek medical attention if symptoms intensify.

What Attracts Black Widow Spiders?

Black Widows are attracted to insects including flies, cockroaches, beetles, crickets, and ants. They also seek abandoned rodent burrows, areas protected from rain and wind, and undisturbed places to build webs and hide including woodpiles, cellars, and crawl spaces.

Learn More About Pest Control for Black Widows

References

1Occupational Safety and Health Administration. (2023). Black Widow Spider. Occupational Safety and Health Administration. Retrieved October 31, 2023, from <https://www.osha.gov/sites/default/files/publications/black_widow_spider.pdf>

2Vetter, R. S. (2020, October). Pests of Homes, Structures, People, and Pets. Agriculture and Natural Resources, University of California. Retrieved October 31, 2023, from <https://ipm.ucanr.edu/PMG/PESTNOTES/pn7442.html>

3University of California, Irvine. (2023). Western black widow. University of California, Irvine. Retrieved October 31, 2023, from <https://nathistoc.bio.uci.edu/spiders/Latrodectus%20hesperus.htm>

4Steve Jacobs. (2022, November 18). Southern Black Widow Spider. Pennsylvania State University. Retrieved October 31, 2023, from <https://extension.psu.edu/southern-black-widow-spider>

5Vetter, R. S. (2017, March). Widow Spiders and Their Relatives. Agriculture and Natural Resources, University of California. Retrieved October 31, 2023, from <https://ipm.ucanr.edu/PMG/PESTNOTES/pn74149.html>

6The University of Tennessee. (2023). The Black Widow Spider. Agricultural Extension Service. Retrieved October 31, 2023, from <https://extension.tennessee.edu/publications/Documents/PB1193.pdf>

7Fischer, A., Ayasse, M., & Andrade, M. C. B. (2018, February 9). Natural Compounds as Spider Repellents: Fact or Myth? National Library of Medicine. Retrieved November 1, 2023, from <https://pubmed.ncbi.nlm.nih.gov/29309619/>

8Entomological Society of America. (2018, January 22). Do Chestnut, Lemon, or Peppermint Scents Repel Spiders? Entomology Today. Retrieved November 1, 2023, from <https://entomologytoday.org/2018/01/22/do-chestnut-lemon-or-peppermint-scents-repel-spiders/>

9U.S. Department of Housing and Urban Development. (2023). Maintenance Guidebook VII Termite, Insect, and Rodent Control. U.S. Department of Housing and Urban Development. Retrieved November 1, 2023, from <https://www.hud.gov/sites/documents/HUDGB7C13GUID.PDF>

10Potter, M. F. (2018, October 4). Eliminating Spiders Around Homes and Buildings. Entomology. Retrieved November 1, 2023, from <https://entomology.ca.uky.edu/ef623>

11Goddard, D. J., Layton, Jr., D. B., & Jarratt, J. H. (2023). Spiders: Brown Recluse and Black Widow. Mississippi State University Extension Service. Retrieved November 1, 2023, from <http://extension.msstate.edu/publications/spiders-brown-recluse-and-black-widow>

12Taravati, S., & Haver, D. L. (2023, August). Hiring a Pest Control Company. Agriculture and Natural Resources, University of California. Retrieved November 1, 2023, from <https://ipm.ucanr.edu/PMG/PESTNOTES/pn74125.html>

13Offerman, S. R., Daubert, G. P., & Clark, R. F. (2011). The Treatment of Black Widow Spider Envenomation with Antivenin Latrodectus Mactans: A Case Series. National Library of Medicine. Retrieved November 1, 2023, from <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3200105/>

14Photo by Tyler C. Public Domain. Resized and changed format. Wikimedia Commons. Retrieved from <https://commons.wikimedia.org/wiki/File:Black_Widow_Spider_with_Eggsack.jpg>

15Photo by AngeliasAtelier. Resized and changed format. Pixabay. Retrieved from <https://pixabay.com/photos/spider-black-widow-insect-halloween-4723710/>

16Photo by Alfried H., Germany. Resized and changed format. Wikimedia Commons. Retrieved from <https://commons.wikimedia.org/wiki/File:Latrodectus_tridecimguttatus.jpg>

17Spider Black Widow Venomous Photo by jgiammatteo. (2017, May 4) / Pixabay Content License. Cropped and added text, shape, and background elements. Pixabay. Retrieved February 16, 2024, from <https://pixabay.com/photos/spider-black-widow-venomous-2282084/>