I hope no one is expecting me to have all the answers, here, because I don’t. I’m more documenting my own research into this subject than offering a definitive answer. But if total ants per square foot of garden created expertise, I would probably be the Ant Queen of Edmonton. (Although not a Queen Ant, obviously, since I am a human, and I could never get them to vote for me.) (Just kidding. Ants don’t vote. Their society is autocratic.)
Are Ants Really So Bad?
I’m not convinced. There are loads of ants in my garden. My compost bin is full of them (a pretty sure sign it’s not getting hot enough to actually compost anything). My raised beds are always overrun with them in the spring. And there are a fair number of them in the ground, as well. I am never sure how hard I should be working to get rid of them. The conventional wisdom is that ants in the garden may be annoying, but they’re not a particularly serious pest. Like worms, they aerate the earth and move organic matter down from the surface. The downsides are that (a) they do sometimes “farm” aphids, which are an annoying pest; ants will set them up on particularly juicy plants, tend to them, and then eat their sugary secretions. Hard-working! And gross! (I kind of didn’t believe this was real until I came across an ant aphid farm on the undersides of some leaves in my garden. And then I was impressed.) And (b) they’re obnoxious little earth-movers, and they’re kind of a nuisance when they move your dirt around and crawl all over the vegetables you’re hoping to eat later.
“Yeah, that’s right. Imma move alllllll your dirt around.”
Even if they’re not exactly up to anything, I’m not crazy about having them in my garden beds themselves. If they would stay in the less-human-y parts of the yard, that would be fine, but if they’re in my raised beds, they’re gonna get — well, I was going to say nuked, but realistically, annoyed. Because in my experience nothing works all that well to get rid of them while still counting as “organic.”
Getting rid of ants organically
Here is a partial list of things I’ve read will either deter or downright kill ants:
- Borax. This is undoubtedly true, as it’s poisonous to ants. It’s also not safe for use around pets or children, so I’m gonna pass on this one. Here’s an interesting article about Borax that helped clear up some confusion I had about it: Getting To The Bottom of Borax: Is It Safe Or Not?
- Diatomaceous earth. This is likely true, as DE is a well-known pesticide, and it is organic, as it is naturally occurring — it’s a type of rock (actually fossilized algae!), ground into a fine powder. SCIENCE! DE is what’s known as a mechanical pesticide because it acts on the insects’ bodies rather than poisoning them — it’s so abrasive that it cuts them up, and they die of dehydration. So that’s pretty horrible if you think about it. I don’t let that stop me, though. DE will act indiscriminately on any soft-bodied insects, including worms, so don’t go crazy. (In past years, I’ve found food grade DE, which is what you want for the garden, at Earth’s General Store.) more info about DE
- Safety note! DE dust is not good for your insides, so wear a dust mask if you’re working with it, and keep pets and kids away from it until it settles.
- Also, if it gets wet it stops working, so you might have to reapply it after rain or watering.
- Cinnamon. I’ve tried this, and it didn’t seem to do anything, but it did make my garden smell delicious. I might have been too stingy with it, given that cinnamon is kind of expensive. I’ve just ordered this half-kilogram bag of the cheap stuff and I’m going to give it another try. At the very least, I will sprinkle it between the layers in my compost and make the bins smell wonderful. You’re welcome, neighbours!
- Flour, or flour with baby powder
- Garlic (as a liquid spray or as a powder)
- Boiling water. I’ve done this one too, and it definitely seemed to stress the ants out, if that’s an effect that can be observed. But I worried that boiling water is also destroying everything else it comes in contact with in the garden, including beneficial insects like earthworms and all those precious bacteria that I know nothing about but that are definitely supposed to be there.
- Coffee grounds. If you did this at the same time as the boiling water, the ants might conclude you’re on a date. Also makes the garden smell delicious.
- Chili powder or other spicy spices
- Tomatoes. Just kidding. But this would be good to have a complete pasta sauce cooking in your garden beds. With ants for protein.
Besides that, there are methods of protecting individual plants from ants or aphids if you find you have an infestation — such as wrapping something sticky (like tape, sticky-side-out) around the stem to keep them from climbing it.
So there you have it, Internet. It seems like almost anything you find in your kitchen can be sprinkled on your ant hills, and it will stress them out, or make them want to go on a second date with you, or kill them horribly. But it will definitely be one of those three.
I’m going to try more boiling water, followed by cinnamon and diatomaceous earth (maybe mixed together?) on the hills in my raised beds and see what happens.
Fine Gardening – Ants Aren’t Your Enemy