I heard copper will repel snails, is this true?

I surrounded my vegetable raised bed by copper pipe, so soon I'll have an answer to my own question. In the meantime, I'm wondering if anyone else has used this method or otherwise have information about it.

Because I live on the edge of a wild canyon, we get literally hundreds of snails and slugs a day. I injured my shoulder last summer throwing them back into the canyon! I don't want to use snail bait and could never put out enough fruit or beer to collect them all. My next move is to try nematodes (spelling?)... Thanks!

 

from what I have been told Copper carries an inherent electical charge which will 'shock' a slug or snail if they try to travel across a length of it.

 

This is basically correct. The Cu+2 ions, being ions, carry a charge that the gastropods do not like. Therefore they're repeled. But there's the problem, they're just repeled. Something better, and probably cheaper, might be to spread something sharp, like crushed egg shells or gravel around the perimeter, they also avoid this. Bird, toads, and lizards love to eat snails and slugs, so if you've go them, let 'em reproduce ;) Good Luck!

 

Hmmmm, I thought it was the inherent toxicity of copper salts that repelled gastropods? Any elemental copper exposed to the elements (water, air, etc.) will oxidize into various salts (the green patina being one). It's that feature that kills lichens and mosses, keeps plants from forming encirling roots in potted nursery stock, kills gastropods, fungicide, and will also kill fish.

I wouldn't have thought the electrical charge phenomenon was valid for a gastropod though it may experience some current due to the 'battery' effect (copper cations & slug anions).

 

Our house wall is harled with gritty gravel that it quite sharp enough to make your knuckles bleed when tying things in. I've seen snails climbing up it, so I'm not convinced by the eggshell approach. I swear they can abseil as well, as I've found them in pots of hostas that were sitting on copper impregnated mats. Collecting was the only way I could have any impact on our population, until the hedgehogs arrived a couple of years ago. Once we'd stopped a kindly neighbour from rescuing them and taking them to the local park, we've had brilliant hostas, even those planted in the ground. Encourage the predators!

 

Thank you all for your responses! I also thought it would be the salts in the copper pipe that repelleed the snails and slugs. Whatever the reason, I hope it works - thus far, I have yet to see a single snail on my lettuce or basil. Last year these items only lasted 2 days in the garden.

As for animals, we have many given that we live on the edge of a wild canyon. But the one animal that would really help, opossums, have never been spotted. Hedgehogs don't live here as far as I know. We have a resident racoon, but he only seems interested in insects under the grass and trash if she can get to it. I have never seen birds eat snails, though I suspect they devour plenty of slugs and flying insects. If the copper pipe works, it would be great news to organic gardeners!

The photo shows the copper pipe (bottom of picutre), flat on the soil in the lettuce garden.

 

Gritty sand isn't very 'sharp' as it is rough. Broken egg shells have very sharp edges that can puncture, rather than be abrasive like sand.

Hmm, small pipe. If you really wanted to believe in the Copper thing (I don't think it's too great, if the snail gets on it and then wants to leave, it's just going to continue going in the direction it was traveling - into your garden)(I think egg shell would be better to try), best would be copper flashing or such, more copper availiable on the surface.

 

It's gravel, not sand, small granite chippings, and it is sharp, which is why I have little faith in egg shells. However, if you've found them to work, I'll take your word for it. It's certainly mentioned it a lot of books, but round here, as we watch the snails on the walls, we laugh hollowly. Wouldn't eggshells get thrown around by the birds and need replenishing frequently, as well? I seem to remember my mother using clinker fron the Aga as a barrier by the greenhouse door, her eggshells all went on the compost heap.
Are hedgehogs a European native?We treasure ours, and the few song thrushes that we get here in the city. When we first moved into this house, more than twenty years ago, there was one that used a rock in the back garden as an anvil, sadly, I haven't seen that for a long time.

 

I know it's a long shot with the copper, as you said, they might just keep going once they encounter it. I'll just have to wait and see if the copper works. The pipe was the best available in long pieces at the hardware store. I'm not yet prepared to use granite or sand, or especially egg shells given the large number I would have to come up with. Everyday I search for the demons but have yet to see even one nearby. They are, however, devouring my sunflower seedlings in the flower garden the moment they appear. For this, I've surrounded them with plastic cups with the bottom taken out. Again, I'll just have to wait to see if this really works. Gardening is like cooking - it's all an experiment! Thanks and let's keep the discussion going.

 

Hedgehogs are found in Europe, Asia, New Zealand & Africa, but not in 'the new world' (unfortunately). In BC, at least, I know that some ground beetles (those 1" long black guys) are keen snail/slug predators and I wouldn't be surprised if skunks liked to eat'em too. I've never seen robins or varied thrushes (our 2 main thrush species) eat snails/slugs, but maybe they're shy about that...

As for copper, I've definitely found that it works. Just last week my crocuses were being attacked before they had a chance to bloom but, after I surrounded each new bud with a ring of copper, all of my crocuses are coming up intact. And as for trapping snails/slugs INSIDE the copper ring, that's a definite danger (I missed 2 slugs in with a hellebore this year) but it's easy enough to spot (uh, the plant is still getting eaten...) and even easier to solve (find the little chompers & pick'em out). No big deal.
-- I'm probably going to grab a roll of copper mesh at Lee Valley this week, but may just settle for a long roll of copper tape instead.
+
Here are a couple more non-toxic suggestions that I found, including a few that I've never heard before (seaweed?): http://www.bbc.co.uk/dna/h2g2/A2876862
-Nic, note the section on 'diatomaceous earth'
-ps: be careful with using coffee - I found that it can go moldy pretty quickly which can spread to or annoy the surrounding plants :(

 

OK, so I did a test. I found 2 large snails (not hard to do around here), and placed them repeatedly on the copper wire. They immediately emerged and turned away from the copper very quickly. This experiment was performed 4 times with the same results! If it works, I will be absolutely thrilled!!!

 

Of course they'll go off it, put them on a branch that's on the ground, they'll do the same :P

 

I tested the stick... they didn't move quite as fast away from the stick as the copper. But I am not sure it's the copper... More tests to follow.

 

I understand, that salt will shrivel them up and kill them through dehydration. I don't know if the brief contact with a small salt filled plastic gutter around your garden (on the canyon side) will be enough. You should take care to contain it, so it will not unduly contaminate your soil.

 

Dry medium such as woodshavings better still sawdust or woodash upset them as well so may be the copper combined with something else. When all else fails ducks. One pair will do wonders however you will need to wire the vegetable patch off and only let them clean out those areas you have finished with. Chooks (chickens) are probably too drastic but a couple of bantam hens are also good contollers of gastropods

Liz

 

Thanks Liz! After running a few more tests with the snails, I decided the fresh planting compost seems to have a big part in deterring the beasts. Once the materials decompose I'll have a huge problem as in the past. My plan is to build a wire frame around the most fragile vegetables, and hope the others can sustain minimal damage between manually removing them.

I would love to have some chickens or ducks but it would be difficult. Besides being great bug and snail eaters, the manure is great for the garden. But the manure is not great for the areas my small children play and sit. The coyotes would probably devour them in broad daylight, and the neighbors would have a fit. My husband thinks it's a crazy idea too, but I may do it one day anyway!

 

Just looking for slug deterrent and I want to attest that slugs definitely have *no* problem with either sharp gravel or shaved wood mulch or sawdust. At least the giant pacific northwest slugs have no problems with those things.

I know this because we have made almost a kilometer of trails on our property using gravel and have beds with very sharp gravel in them both have slugs chugging along right across them. Also we generate a lot of sawdust cutting up fallen trees and we use shaved wood mulch everywhere and both have had slugs running across them.

I'll try the copper thing out. It will be an easy test here because the back of our property is swampy and you literally can not walk two feet without running into several slugs (mostly the black kind but a few of the greenish brown ones as well and some snails here and there). We planted a lot of stuff along the trails and they've gone to town on it. Every day we go out and flick slugs off the plants so I should be able to determine if this works in about one day and will report back, just have to get my hands on some copper.

 

JCardina: I'm VERY interested in learning about the results of your test. So far, I've seen no snails at all in my small vegetable garden, but have found several slugs munching away.

I'm using copper pipe intended for plumbing from my local hardware store. I bought a 25' roll, but would recommend shorter pieces to better set it up flush on the ground.

Good luck and let me know!

 

The other thing that works wonders is a pair of guineafowl. Your yard will be pest free in two days, and they won't go after the plants.

I've found copper to be very effective against slugs and snails, but I buy a fine mesh about 5" tall and stretchable, that I can flex easily around the corners of my beds. I think Lee Valley Veritas was where I was buying it... I tried copper pipes but this is soo much better, since they'd have to climb it to get at the plants.

 

I have had good luck with copper. I used it around pots but it gets expensive (I use the rolls that I buy in garden store or catalogs)
I have found that diatomaceous earth around the seedlings does protect them. Since I water with a drip system and it doesn't rain often in Los Angeles I can don't need to reapply often
I am also over a canyon and carry buckets full of snail and slugs down the hill. I know it is useless and I take the same ones back every day.

 

I was *very* excited at the prospect of using seaweed. It seems to make perfect sense, it's salty through and through and salt kills slugs so it should do the trick.

Today we went and collected a bag of fresh seaweed at the beach, surrounded our most attacked plants with it and found a slug on the trail so we surrounded it in a ring of seaweed as a test to see if it would still be there in the morning. Almost right away the slug turned towards the seaweed, oozed over to it and started *eating* it!!

It wasn't just a taste test, it kept at it. About an hour later we came back and the slug was gone completely despite being surrounded in seaweed and another smaller slug had come across it and was eating the seaweed as well from the outside of the ring. Either we have some super slugs or the reports of it being a good slug deterrent are *highly* overrated, however if you want to attract slugs and feed them... :)

I don't know about the green slugs, we have those as well but they are a very minor problem compared to the black ones. The green ones are *much* larger but they are very rare on our property.

See attached picture of slug in action eating seaweed. It ate some from all sides of the ring but seemed to prefer the light green stuff the best, you could see it sucking it in. Also note the sharp rocks and gravel that our paths are made up of that they regularly crawl along so I think that's a bit of a myth as well.

So far I'm down to trying copper at this point.

 

If you want to attract snails/slugs to one place where you can deal with them efficiently put empty half grapefruit peels upside down in the garden and look underneath the next day. I have collected up to 20 per peel. Orange peels also work.

Bob
Vancouver west side

 

hello

i once had slugs all over the place as we had mud brough from a river bed. to one cup salt add a little turmeric powder and sprinkle on the sides. i did this close to our building so that it does not enter it as...ooops we often ...skated on them...!! luckily they vanished with common salt.

sathya

 

Ok, tried the copper trick. We found a roll of copper strapping at the hardware store. It's flexible, about a half inch wide and is not coated with anything, it's bare copper.

I made a corral out of it about a foot across and connected at the open end, walked down the trails in our back property and immediately came across a big green banana slug. I tossed the ring over the slug so he was trapped inside. He continued on his way, came to the copper ring and slimed right over it like it was nothing. I put it in front of him to block him and he checked it out for a second then crawled right over it.

So copper has zero effect on our large banana slugs we have here on Vancouver Island.

To summarize:
Sharp gravel - no effect.
Seaweed - no effect other than they love to eat the stuff.
Copper - no effect.
Wood mulch (sawdust or shredded mulch) - no effect.

We have millions of slugs here I can test anything but I won't pour salt on them because I think that's cruel. Also I can't use salt around my plants for obvious reasons.

Any other suggestions?

 

pick 'em up with a fork and fling 'em back into the forest?