Killing cockroaches with boric acid v borax!

We live in Queensland. We have cockroaches. Lots of cockroaches! Why the NSW rugby team is called the Cockroaches is a mystery to me - surely ours are not only bigger but more plentiful??? At any rate, I don't like living with them (and I'm quite sure they  are not so fond of me at the moment!!) and I have been going through the usual gauntlet of sprays, solutions and bombs to get rid of them...

But I'm not so keen on the chemical aspect of all this spraying and bombing. I hate the smell and can almost feel disease and cancer growing in me every time I spray. I'm OK with the resident cockies getting a lungful of chemicals and then keeling over but I feel its impolite (and probably illegal) if my guests and family members do the same thing!!!

We went through a faze of killing them by hand (and flyswatter and rolled up newspaper and underfoot) but its hard and frustrating work and it probably was only culling the dumb and slow ones - leaving the smart fast ones to breed!!!

The Internet has a million suggestions on how to kill roaches -

Here's what I did...

First - we did the dishes EVERY night. And wiped the benches. And generally tried to keep our kitchen gleaming and clean. Cockies hate that! They love damp crumb laden kitchen benches and cupboards.

Then I got onto Amazon and bought some boric acid online and then went down to the supermarket and found 500gm Borax on the laundry shelves for $3.50. My research didn't give me a definitive answer as to wether they were the same thing or if they worked the same. So for a few extra dollars, I hedged my bets.

I have since spoken to a friend of mine who works with chemicals for a living and he said they both have Boron in them and that's whats going to kill my wee pests. Boric Acid seems to have a higher concentrate and is finer and so harder for the cockies to step around or even nibble around. He likened the Borax to finding gravel in your food - its easy to spit it out - and that's what the cockroaches will do when they find it in their dinner! However if they walk on Borax and it stick to them, they will "lick" it off.

Borax granules on the left and Boric Acid powder on the right.

I did a few things- again hedging my bets. I sprinkled the Borax in the corners of my cupboards, under the fridge, under the rubbish bin and into every crack and crevice I could find. I also put some under cabinets, under the bathroom sink and every hard to reach place I have chased a cockroach into over the last few years.

When the Boric Acid arrived in the mail. I cleaned up the Borax that was obvious and replaced it with the much finer Boric Acid. Cockroaches groom themselves (that's how they get that dark brown evil looking colour) and if they have fine particles of the Boric Acid on them, they will, just like a cat, lick it off, swallow it and die! Please don't leave this stuff ANYWHERE your children or animals can get to it. It is an ingestant and will make animals and people very sick if they get inside them. Cats are especially vunerable as they will lick any Borax or Boric Acid they get on them off and swallow it. It can kill them. It dries the coackroach out from what I can gather...

Next I made this bait. If the cockies are as smart as they seem to be and walk around my Borax and Boric Acid sprinkles, then I'm hoping to attract them with this mixture.

I put 1 tablespoon of sugar into a small container and mixed in 1 teaspoon of milk. Then I added 1 teaspoon of Boric Acid and mixed it all together.

This makes a paste that I then put onto bits of cut up takeaway container lid.

These I flicked under the fridge, filing cabinet, under some cupboards, behind the loo and anywhere I thought the children wouldn't see it or the cat wouldn't be able to get at it.

This isn't an instant cure. But of all the things I have tried, this has the least impact on my health, is cheap, and best of all seems to be working!!! Most mornings I am finding at least one dead cockie on the floor and this morning when I vacuumed, I unearthed another four that were underneath things I don't look under on a daily basis. I am starting to find them dead in the downstairs laundry and in the kids rooms where I haven't put any baits- just in case.

That tells me that they are getting into the baits and walking over the sprinkles and then running back to their hidey holes to  die. As these cockroaches have been poisoned, I don't give them to our chooks or throw them out into the garden. I don't want to kill any birds or whatever else feasts on dead cockroaches. I put them in the bin or the compost.

I'm pleased with the results but implore you to be very careful with both Borax and Boric Acid if you try it so that no one but them cockies gets hurt!! The instructions that came with the Boric Acid said to replace these baits every 3-4 weeks. I reckon I have seen more dead cockies in four weeks using these baits and the sprinkles than I have with commercial insect killers - Including the Bombs.

Apparently it will deal with ants as well... But that's another post!

June 2013 Update:
Its been a year or so since I wrote this post and it continues to be one of my more popular entries - obviously I'm not the only one with a cockroach problem wanting to resole it naturally!

After about 3 weeks of starting with the baits the cockroach population had dropped dramatically. I changed all the baits - just in case and kept changing them every month religiously for about 6 months and tracked the dates in my diary. And you know what? We simply don't have any cockroaches anymore! The only time I change the baits these days is when I actually see a cockroach which reminds me... But as I'm writing this, I am struggling to remember when that was....

The only real improvement I have made is to use milk bottle lids as sometimes the mixture is runny and runs off the cut up lid making it tricky to transport to the place I want to put it.

Update June 2014:
We have so few cockroaches now that we only remember to make new baits when we actually see a cockroach. I still have the original bag of boric acid as you only need a teaspoon full each time you make it up. I am amazed at how well this works for so little money!

We struggled with cockroaches for so long and now they are simply not an issue in our house! If you have a cockroach problem - try this - it worked for us!


Good luck - let me know how you went! - K xx



Score card:
Green-ness: 3/5 Its still chemicals that we are spreading around our house...
Frugal-ness: 5/5 Super cheap and this stuff lasts for a long time. I reckon I will get at least a year of cockroach killing out of my $8.50 (or maybe 3 or 4 at the rate I'm going through it! - June 2013)
Time cost: 5 minutes to make up the bait and distribute it and another 10 to sprinkle the Borax and Boric Acid in hard to reach places. Plus another 10 minute to vacuum up what might be walked on by the cat.
Skill level: Easy - just need to be careful you don't inhale or ingest this stuff.
Fun -ness: Not much fun killing things, but I have to admit to a bit of a thrill each time I see a dead cockroach these days...