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What household item will kill a black widow?

Black widows are venomous spiders found throughout many parts of the world. Although their bites rarely kill humans, they can cause severe pain, swelling, nausea, and muscle aches. Many homeowners seek safe, effective household remedies to kill black widows found in and around their homes. Common questions about killing black widows include: What household items work best? How quickly do they kill the spider? Are these methods humane? This article explores the most effective household items for safely killing black widows.

Household Chemicals

Many common household chemicals are effective at killing black widows. Products containing chemicals like pyrethroids, permethrin, allethrin, tetramethrin, resmethrin, and sumithrin act as neurotoxins on insects. When sprayed directly on spiders, these chemicals interfere with their nervous systems, quickly paralyzing and killing them. However, some risks come with using these types of products:

  • Chemical sprays can be dangerous if inhaled by people or pets.
  • They may not lead to a humane death for the spider.
  • Spiders could crawl away and die out of sight in the home.
  • Dead spiders may leave behind egg sacs that could hatch.

When using chemical sprays, it is important to carefully follow all safety precautions listed on the product. Only use them in well-ventilated areas and avoid breathing in sprays. Wear gloves and wash hands after use. Never spray chemicals directly into spider nests or webs, as this risks spraying spider babies hidden inside.

Common Household Chemical Spray Products

Product Active Ingredient Notes
Raid Ant & Roach Killer Sumithrin, piperonyl butoxide Works quickly to kill spiders.
Ortho Home Defense Bifenthrin Long-lasting; use only outdoors.
Hot Shot Bed Bug & Flea Home Insecticide Lambda-cyhalothrin, piperonyl butoxide For indoor and outdoor use.

Soap and Water

Dish soap mixed with water can be an effective homemade spider spray. The fatty acids in soap dissolve the spider’s exoskeleton, killing it quickly. Mix about 2 tablespoons of dish soap with water in a spray bottle. Agitate the bottle to create soapy suds. Spray directly on spiders to quickly immobilize and kill them.

Advantages of using soapy water include:

  • Safer for use around pets and humans compared to harsh chemicals.
  • Products are readily available in most homes.
  • Inexpensive and simple method.

Spiders hit with soapy water will die quickly, usually within minutes. Avoid spraying nests or webs, as this could kill spiderlings. Rinse dead spiders away with plain water. Soap solutions are safe for the environment when rinsed away.

Alcohol

Spraying black widows directly with rubbing alcohol is lethal. Alcohol desiccates or dissolves the spider’s tissues, destroying vital organs and quickly killing it. Make a spray by mixing 2 parts 90% isopropyl alcohol with 1 part water in a spray bottle. Shake well before use. Spray spiders until thoroughly coated for fast knockdown and kill.

Rubbing alcohol is convenient and inexpensive, available in any drug or grocery store. It kills spiders humanely on contact, but must be sprayed directly onto the spider’s body for efficacy. Alcohol solutions have little residual effect, meaning they won’t continue killing after application. Rinse dead spiders away with water.

Advantages & Disadvantages of Alcohol Sprays

Advantages Disadvantages
– Very effective fast knockdown and kill – No residual killing power
– Typically readily available in homes – Can be flammable
– Inexpensive – Spiders could crawl away and die out of sight

Diatomaceous Earth

Diatomaceous earth (DE) is a non-toxic powder made from fossilized algae. The microscopic razor-sharp edges of DE cut into an insect’s waxy exoskeleton, causing dehydration and death within 48 hours. DE can be used to safely kill black widows:

  1. Wear gloves, safety goggles, and a particle mask when handling DE.
  2. Use a duster applicator to apply a fine layer of DE along baseboards, window sills, and anywhere spiders are frequently spotted.
  3. DE has no odor and causes spiders to die within a couple days after contact.
  4. Reapply DE after cleaning or vacuuming an area.

DE provides effective control and is safe for use around children and pets when applied correctly. It can help prevent future infestations by killing spiders that contact treated areas. Avoid breathing in the dust when applying DE.

Tips for Using Diatomaceous Earth

Use Precautions
– Apply in closets, under appliances, along walls – Wear a mask to avoid breathing in dust
– Dust crawl spaces, attics, and basements – Keep pets and children away during application
– Reapply after cleaning treated areas – Avoid contact with eyes and lungs

Canola Oil

Pure canola oil applied directly to a black widow can kill it by coating its breathing holes and causing suffocation. This method takes some time but can be effective. Follow these steps:

  1. Transfer pure canola oil to a narrow container for easier application.
  2. Use an eyedropper or pipette to slowly drip oil onto the black widow’s body, covering it completely.
  3. The spider will become immobilized and die from suffocation within 3-4 hours.
  4. Once dead, use a paper towel to remove the spider.

Canola oil is non-toxic and generally safe for use around pets and humans. Avoid getting oil on furniture, carpets, or other surfaces that could be damaged by grease stains. Canola oil has no residual killing effects after application.

Pros and Cons of Using Canola Oil

Pros Cons
– Non-toxic and pet safe – Very slow kill time
– No strong odor – Messy oil could stain surfaces
– Typically available in most kitchens – Spider could crawl away and die out of sight

Hot Water

Pouring boiling water onto spiders is an age-old home remedy for pest control. The thermal shock immediately kills spiders by essentially cooking them inside their exoskeleton. Here are some tips for safely using boiling water to kill black widows:

  • Bring a pot or kettle of clean tap water to a rolling boil on the stove.
  • Have a large container or bucket ready nearby to catch runoff water.
  • Carefully pour the boiling water in a directed stream right on top of spiders to scald them.
  • Use approximately 1/2 cup of boiling water per spider.
  • The water will immediately kill spiders and run safely into the catch container.

This method is very effective for safely eliminating black widows hiding in garages, basements, attics, and other areas where chemical use may be risky. Avoid pouring near sensitive surfaces that could warp from steam or heat. Take precautions against scalding yourself with splashing or boiling water.

Safety Tips for Using Boiling Water

Precautions Protective Gear
– Work slowly on level surfaces – Heat-resistant gloves
– Have catch container ready – Eye protection
– Keep children/pets away – Long sleeves & pants

Adhesive Traps

Sticky adhesive traps can be an effective and convenient way to catch and kill wandering black widow spiders in the home. They contain no toxins and work through the following actions:

  1. Black widows get stuck to the glue when they crawl across the traps.
  2. The glue holds the spiders in place until they die from exhaustion, dehydration, or starvation.
  3. Traps can then be discarded along with dead spiders.

For best results, use many small traps along walls, in corners, under appliances, and anywhere spiders are frequently spotted. Check and replace traps often to remove caught spiders. Adhesive traps have no residual killing effects after use.

Tips for Using Sticky Traps Effectively

Do Don’t
– Use many small traps instead of few large ones – Place traps in easily visible locations only
– Place traps along walls and hidden spider paths – Allow traps to become covered in dust and debris
– Check traps daily and replace often – Place near food prep areas or children’s reach

Vacuuming

A powerful handheld or shop vacuum can suction up and kill black widows quickly and efficiently. Equip the vacuum with a hose attachment and crevice tool to access small spaces and capture spiders. When vacuuming spiders:

  • Keep the vacuum nozzle about 6 inches away to avoid spider escape.
  • Use the crevice tool to extract spiders from corners, gaps, and tight spaces.
  • Aim suction directly at the spider’s body to lift and trap it inside the vacuum.
  • Seal and dispose of the vacuum bag or contents after use.

Vacuuming is highly effective for killing spiders hiding in garages, sheds, basements, attics, and similar areas. Avoid using vacuums to suction up spiders near sensitive surfaces that could get scratched. Wear protective clothing in case hidden spiders try to bite when disturbed.

Safety Tips for Vacuuming Spiders

Precautions Protective Gear
– Work slowly to corner spiders – Rubber gloves
– Keep nozzle 6+ inches away – Safety glasses
– Seal and dispose of vacuum contents – Dust mask (if needed)

Crushing Manually

Black widows can be killed by manually crushing them underneath an object such as a heavy book, boot heel, or other sturdy item. Take extreme care with this method for several reasons:

  • Live black widows may bite in self-defense when crushed.
  • Venom can transfer through protective clothing.
  • Babies may be hidden nearby.
  • Spider parts can stick to surfaces.

To safely crush black widows:

  1. Wear heavy boots, thick gloves, long sleeves & pants, eye & face protection.
  2. Have object ready to crush spider after locating it.
  3. Forcefully stomp or smash object down on spider.
  4. Avoid crushing egg sacs which could contain hundreds of babies.
  5. Carefully clean any spider remains off boots or crushing object.

Manual crushing is a last resort only if safer options are unavailable. The risks of bites and contact with spider parts often outweigh the benefits.

Safety Gear for Crushing Black Widows

Protection Examples
Thick gloves Rubber dish gloves, leather gloves
Boots or shoes Rubber boots, leather work boots
Eye protection Safety goggles, face shield
Long sleeves & pants Denim, canvas, thick fabrics

Conclusion

Black widow spiders can certainly cause harm with their venomous bites, but they can be safely controlled or eliminated using common household items. Chemical sprays, soapy water, rubbing alcohol, and diatomaceous earth can all effectively kill spiders on contact when applied correctly. Traps, vacuums, boiling water, and manual crushing also end spider problems.

Prioritize safety for yourself, family, and pets when using any home spider control methods. Always exercise caution near black widows to avoid bites. Focus control efforts in hidden, undisturbed areas where spiders nest and breed. With smart precautions and consistent control methods, black widow spiders can successfully be managed around the home.