What is a good homemade ant killer?
Quite by accident while away from home, I found out that
toothpaste will kill ants immediately on contact (it was all I had
available when I noticed an invasion one night.) These were very
intrepid and adamant ants, even resistant to squashing. But when,
in desperation, I smeared a glob along their marching path, they
stopped dead in their tracks. I don't know if different brands have
the same effect, but what I had on hand was some cheap off-brand
stuff. It also kept them at bay when I globbed it around their
entrance hole, but I don't know if it kept working after the
Other than that, I've seen numerous recipes for homemade bait,
with the active ingredient being boric acid (Borax.) You mix it
with sugar, honey, molasses, or any other sweet to bait the ants,
then they take it back to their nests and the boric acid poisons
the entire colony. The ratio of boric acid to sweet ingredients
varies widely in the recipes, and I think you just need to
experiment until you find the recipe that works for your variety of
ant. I'd start with a cup of honey or corn syrup with 2 Tablespoons
of Boraxo mixed in first, then see how the ants take to it. If
there's too much Boraxo, they might not take the bait, but if
there's too little, they might gobble it up without dying. Some
ants like meat/protein, so you could also mix the Boraxo with bacon
grease or peanut butter.
With Boraxo, you have to be careful that it's kept out of reach
by kids or pets. One idea I read online recommended putting the
bait in plastic containers with holes punched for the ants to get
in, but I don't know of any toddler who can't open a yogurt
container. I'd just be really careful if I had kids around. Make
sure the ants can get in & out, but not the kids or Fido.
Another thing I've read for a bait they take back to kill the
nest is using baker's yeast mixed with a sweet. The idea is that
the yeast will expand and kill them when they eat it. I don't know
if it works as well as the Boraxo recipe, but the advantage is that
yeast won't poison kids or pets.
There are other things that work, if you just want a spray
poison to kill them immediately (such as bleach water, ammonia,
vinegar), but it seems worth it to take the time to bait them so
they'll eventually die off and never come back.