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Best way to kill/repel cockroaches?

  1. Nov 3, 2013 #1
    Hello, I have a mortal fear of cockroaches and they are everywhere but I can't fumigate because my gran doesn't want to. So what is the best way to kill/repel cockroaches? Thanks.
  2. jcsd
  3. Nov 3, 2013 #2


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    Nothing if they are established and you don't spray (or move). Even with aggressive fumigation, their population follows an exponential decay similar to radioactive decay. e.i. a "population half-life"


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  4. Nov 3, 2013 #3
    Thanks, I am familiar radioactive decay. Didn't think about it applied to 'roaches though.
  5. Nov 3, 2013 #4


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    You're never going to get rid of them; unless you fix the reason they're there to begin with. Seal up food, fix leaky pipes, take out the trash frequently, seal up cracks in the wall. You can get boric acid and make roach traps, but this will do nothing then curb their numbers.

    You need to fix the reason why they're there, and get them to leave due to starvation/dehydration.
  6. Nov 3, 2013 #5
    This house is pretty old/leaky/full of cracks. Even when there is no food they chew on our books.
    boric acid is a good suggestion though. Are they scared of anything? I heard that theyn fear chrysthananums because of the pyrethroids.
  7. Nov 3, 2013 #6


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    Because that's food. Fix up the house.
  8. Nov 3, 2013 #7


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    I use wasp spray when I see a roach in the garage. It's nice because you can get from several feet away.
  9. Nov 3, 2013 #8
    with us at night they are so many, and you can actually here them and see them darting out the corner of your eye.
  10. Nov 3, 2013 #9


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    They are scared of being in places where you don't find them. Clearly, those places don't include your house.

    Maybe the quickest solutions would be first kill your granny, and then fumigate the house :devil:

    But grannies can be nearly as hard to kill as roaches.
  11. Nov 3, 2013 #10
    Burn them with a blowtorch!!!!
  12. Nov 3, 2013 #11
    Clean the whole house. Use sprayers around the wet/humid areas where cockroaches are active at night. Sometimes I wake up at midnight for WC, I step on one fellow inadvertently and think it is just his lucky day to end his life too soon
  13. Nov 3, 2013 #12
    They've become less scared of me. They don't run unless I pick up something to hit them with and they seem more resistant to bug spray. Evolutions a B!t*#
  14. Nov 3, 2013 #13
  15. Nov 4, 2013 #14
    I have recent experience in this matter: I just finished renovating my bathroom and had the pest before I did the work. I found several holes in the wall plates (2x4 on the floors) that plumbers had drilled for piping. I sealed up all the holes and no longer see them in my home. Also, as mentioned above, keep your home, kitchen especially, very clean and seal up everything so they have no food. If your home is elevated, go underneath it if you can do so safely, and look for piping entering the floor or look for any holes and seal them up.
  16. Nov 4, 2013 #15
    My cat DESTROYS roaches.
  17. Nov 4, 2013 #16
    Whoooa... You have an epic cat. Mine attacks dogs and walks with lynxs (once)(you get them were I live) but does nothing to help me. He eats vegatables, what kind of a cat is that?
  18. Nov 4, 2013 #17


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    A vegan
  19. Nov 4, 2013 #18
    Winter is coming. Do you live in a climate where the temperature drops well below freezing at night, say to -6C (21F) or lower? If so, shut off the water and heat and take a trip somewhere. Three or four nights at those temperatures might do the job. (It's up to you whether you take your grannie with you or leave her there.)

  20. Nov 4, 2013 #19

    Vanadium 50

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    Not in the Southern Hemisphere, unfortunately. (Where the OP is)
  21. Nov 4, 2013 #20
    Right you are V-50. Lethargy runs amok as temperatures average 27 Celsius.
  22. Nov 4, 2013 #21
    Too bad. 90% of the world's population live in the Northern Hemisphere, but YOU have to be different! Well, maybe my advice will help someone.
    Last edited: Nov 4, 2013
  23. Nov 4, 2013 #22
    I'm not happy about it either. If I get raped and killed here there is only an 11% chance of my murderer being caught.
  24. Nov 4, 2013 #23


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    Eat them, they are good source of protein.
  25. Nov 4, 2013 #24
    Assuming that all animals were the same size cockroaches would be the fastest animal. (or so I hear)
  26. Nov 4, 2013 #25


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    Borax, though I'm not entirely sure of how safe it is for other animals. I have roaches in my apartment myself.

    They spray once per month
    I meticulously clean all surfaces
    no standing water, no food left out
    borax sprinkled along every baseboard and stuffed into every nook and cranny

    I'm sure I still have thousands, somewhere. But this has made it so I only see one or two every few weeks.
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