what do slugs NOT eat?

I've had minor slug damage in the past, but this year we seem to have had a slug population explosion. I transplanted something like 150 lettuce, broccoli, and collard seedlings, only to have the majority of them completely demolished by slugs. In assessing the damage, I noted that the beds that had wood chip mulch were untouched, whereas the beds with leaf mulch were heavily damaged. A closer look revealed dozens and dozens (and dozens) of tiny quarter-inch baby slugs nestled in every nook and cranny of the leaf mulch.

I put out some beer and yeast traps as an experiment, and they do seem to work--not perfectly--but I think I may be able to salvage the new transplants. The problem is that most of my beds were mulched with leaves for over-wintering, but now I need to get them planted and I'm obviously concerned. I'll continue with the traps, but also think I need a more integrated approach if I'm not going to lose most of my garden to slugs. I know folks have success with ducks, but we're duckless at the moment, so that will take some planning and coordinating, i.e. it's a future solution. I need a plan I can begin to implement now.

Another thing I noticed, was that the slugs have left the horseradish alone, and while I found them on the chicory and volunteer violets, they haven't done much damage. Which leads to my question:

What do slugs NOT eat?

I'm turning to all of you observant gardeners out there - in your experience, what do slugs seem to leave alone? If I can combine your observations with slug traps, garden bed clean-up, and a change of mulch, hopefully, I can get a harvest this year.

Howdy,
I don't remember where I read it, but my slug deterrent over the years has been crushed egg shells. Slugs can't handle the sharp edges. I was having a real hard time in my strawberry patch, heavily multched. I just threw crushed egg shells in there and for years now I get gallons of strawberries and very few slugs. Any where I am mulching in my garden I throw crushed egg shells. This seems to work for me, and my friends LOVE my strawberries...

Thanks Randal! I'll add that to my integrated plan.

Cut blackberry vines or other pointy plants also work, maybe burn the ends though so prevent any cuttings from taking root.

I have childhood memories that strawberries that were surrounded by parsley were not eaten by the slugs.

Parsley! Thank you R!

T, that would be some pretty prickly mulch!

I've not convinced that slug traps do much more than make you feel you're getting revenge on the little blighters.  Getting some sort of balance and creating the right environment for slug predators would be the optimum solution.  Amphibians such as frogs and toads are one group that are supposed to eat them, as are ground beetles.  One thing I wonder whether would work is sunken beds around vulnerable crops, so that beetles fall in and are less able to get out, sort of like reverse raised beds with edges.  I have to say I haven't tried it yet though.  
When I first came here I had a lot of trouble with slugs, almost everything I sowed was eaten.  The things I found helped was transplanting strong little plants, rather than sowing direct.  Tasty plants such as cucubits can be protected with a little collar in the form of a cut down plant pot.  Here is a picture of some results of my trial of defences using lupins as a sacrificial bait.  



The full test is here.  You can see the eggshells were not effective at all in the long term for me despite a really thick layer, but a barrier, even without copper tape was reasonably effective.

These days I seem to have a better balance with the slugs, although that might be because I sow far fewer seeds outside these days, and slugs are less of a problem in the drier polytunnel.  It would be interesting to repeat the lupin experiment now though....

As far as plants that slugs dislike as opposed to ones they like, their tastes unfortunately coincide with ours.  I don't think they like tomatoes, or most herbs. I wonder whether my interest in perennial vegetables was partly inspired by trying to get a headstart on the slugs - since the plants are bigger, or grow away faster, the slugs seem to affect them less than poor little seedlings

Nancy, so far they have left my tomatoes alone! The collard seedlings though, even with the traps and cutworm collars are still targets. I'll have to try making some out of plant pots. Maybe taller and sturdier would help. The beer and yeast traps seem to help, but I reckon there are just too many of them.

With other critters, we've noticed that populations can fluctuate significantly from year to year. One year, we were inundated with spiders. We don't mind spiders, but repeatedly walking into face-first into webs gets annoying. The next year, hardly any spiders. I don't know if it will be the same with slugs.

I'll have to add a few toad habitats to the garden too. In fact, I think there's a badge bit for that!

If eggshells work, I wonder if the crushed oyster shells sold in giant bags for chickens would do the same job. Hmmm...

Douglas Alpenstock wrote:If eggshells work, I wonder if the crushed oyster shells sold in giant bags for chickens would do the same job. Hmmm...

Do these have sharp edges? I never buy these because I feed my crushed eggshells back to my chickens. I am going to try some in my strawberry bed, however. I know what doesn't work for slugs - diatomaceous earth. They didn't like getting sprinkled with it, but it didn't stop them.

Douglas, if you experiment, let us know what happens!

Douglas Alpenstock wrote:If eggshells work, I wonder if the crushed oyster shells sold in giant bags for chickens would do the same job. Hmmm...

Yes, crushed oyster shells work just as well as crushed egg shells (and so does saw dust)... Anything that is in particle form and will stick to the bottom of the slug or snail, it’s kinda like a tire spinning in mud, little to no traction, much harder to move. They hate that.

I like sawdust paths in the garden. Slugs and snails hate it, the sawdust decomposes and eventually becomes soil (after serving to deter slugs and snails). Sawdust is cheap and easy to get...

I also love copper. Slugs and snails hate copper, but if you use it, it needs to be wide enough that they can’t arch over it (2+ inches wide).

Slugs and snails will often over winter in leaf debris, so it’s better to compost the leaves and mulch with wood chips or organic straw and stuff less likely to have them hidden inside.

I was watching a video where a farmer swears by daikon radishes and uses them in his cover crop mix. He said it leaves a nice deep narrow hole, breaks up hard soil compaction, and kills slugs and snails. He pulled a big ol daikon out of the ground, it was about 26 inches long and he pointed to the skin on it where a slug had noshed on it a bit. He said the outer skin on the daikon is sweet and mild and exactly what slugs and snails love to eat, but right under it is the inside of the radish which is very high in sulfur and when the slug or snails gets into that part, it kills them. And he zoomed in on the shallow spot where the slug had munched and then stopped eating.

Now I haven’t confirmed his claim, but I am planning on testing that out. The daikons were doing a great job as part of the cover crop, and he was just leaving it all in and doing no till planting on top after rolling it all, and then using a seed drill.

So you might want to consider growing a little patch of daikon to see if it does indeed kill slugs and snails. If it doesn’t work, they are still pretty tasty and nice for salads or pickles and what not. I doubt I could find that video again, but it was an interesting little tidbit that might yield something cool.

Good luck!

Paul, I pulled 37 baby slugs off a daikon plant last night. I also have a large patch of it that I think has been acting as a large breeding site for them. The slugs have been migrating from that patch into my young greens. I'm at my wits end on dealing with these slugs. Right now, I have been watering in the evening every other night to help draw them out of the ground and then I hunt them all for about 2 hours in the early night. I'm also using Sluggo. I live in the Pacific Northwest and I just can't catch a break with these things. I'm also putting out fresh crushed greens in the paths to help bait them for easier murdering. I haven't tried placing pots around the young plants yet. I'm hoping that the slugs will be less of a problem next year if I do some serious slug killing in the fall. Otherwise, I might just quit planting annuals all together.

What they LOVE : most baby plants, anything cabbagey, spinach, cucurbits when they are young enough to nibble at the stems and chop them off just below anything that can regrow. Also squashes that sit on the ground in wet weather.

What they dislike : tomatoes, & probably other solinaceae

What they don't seem to be keen on :  things with red leaves, like beetroot, red lettuce (not crazy about lettuce anyway unless it's a tiny baby), alliums, radishes...

Peas seem to please snails more. Not sure about beans.

I used to have trouble with slugs, things seem to have calmed down, maybe because I use less leaf mulch, maybe because my soil has changed, maybe because the climate's drier ?

Still, I sow everything in pots and only plant it out when it's big enough to cope with slugs.

When the pots are outside, I put them up in the air (more difficult to smell for slugs) on metal grills or metal tables. They virtually never climb up those.

I no longer really bother with eggshells, nettles, etc, too fiddly and not really efficaceous enough, except that I put a litle collar of cat's fur felt (that's what I've got, sheep's wool is supposed to work, too) around the lower stems of cucurbits, cabbage family (notably Oleracea) and anything else I think might get damaged when I plant it out.

I have a cold frame on the ground, which I only ever use for tomatoes. This year I've put some grass trimmings in there to ferment and warm it for warmer nights, I've put some flower seeds & stuff in there and so far the slugs seem to be unwilling to tackle the fermenting grass (but it's been very dry so not a very good test).

I also vertically garden, which helps, and am going to look into making a strawberry tower this year, in the hope of getting more strawberries for me and sharing less with whatever wildlife eats them (even the blackbirds stay mostly on the ground).

In my not very systematic experience slugs have a much lesser appetite for things that are purple instead of green. Ie. red cabbage, certain red-colored lettuce and amaranth varieties, etc.

Leigh Tate wrote: know what doesn't work for slugs - diatomaceous earth. They didn't like getting sprinkled with it, but it didn't stop them.

DE in the garden is a bad idea, as it will indiscriminately kill any insect that comes close and you will lose lots of beneficial wildlife.

What works in my garden:
Swiss chards (also spinach, hardly any damage), beets, onion family; for peas and beans I have to watch out when they are small. Cucurbits are the most endangered plants, cruciferous (like pak choy, cime di rapa) come next.
I am breeding a salad (in the third generation now) that is apparently not very appetizing for slugs, so I will stick with it.

Regarding solanacea like tomatoes: In bad periods slugs will nibble leaves and fruit. Even worse with egg plants, last year I was not able to harvest.
Peppers are also in danger in wet spells.

All in all, I am keeping up with them now - mostly - I encourage a diverse habitat, I do have leopard slugs and bugs, and I go out on damp evenings to mechanically reduce slugs.

Our NW CA native banana slugs eat everything, living or dead, but redwood. Undoubtedly they have co-evolved. First of all, redwood is almost impossible for anything to digest on its own (no single insect, mite or fungus species can kill it, but it also supports more diverse soil life than any other plant), and it can make more chemical compounds than an acre or diverse wildflowers can combined. From the banana slugs’ perspective, it provides more biomass/food in its understory than any other plant could, as well as shade and moisture (trees condense 2x the precipitation they consume, or more). So banana slugs eating redwood would be like going to an all inclusive resort in paradise and eating the buildings.

I would bet western red cedar has a similar relationship to banana slugs farther north in the pacific NW, and that european slugs have a similar relationship to climax canopy trees from their native environs. Slug manure is undoubtedly good for soil fertility, and I would speculate slugs are evolved to do a weed and feed service for the canopy trees that provide them shade, shelter and moisture. Not really a solution, but the predators that also get shelter, shade and water from these forests when undisturbed would keep them in balance. I would lean into slug predator habitat, look on the fertile side that they are at least leaving rich manure behind, and realize that our “pests” exist because we give them habitat and often fail to allow their predators to keep up by intervening in a way that knocks down their population more than the pests’.

Dj Cox wrote:Paul, I pulled 37 baby slugs off a daikon plant last night. I also have a large patch of it that I think has been acting as a large breeding site for them. The slugs have been migrating from that patch into my young greens. I'm at my wits end on dealing with these slugs. Right now, I have been watering in the evening every other night to help draw them out of the ground and then I hunt them all for about 2 hours in the early night. I'm also using Sluggo. I live in the Pacific Northwest and I just can't catch a break with these things. I'm also putting out fresh crushed greens in the paths to help bait them for easier murdering. I haven't tried placing pots around the young plants yet. I'm hoping that the slugs will be less of a problem next year if I do some serious slug killing in the fall. Otherwise, I might just quit planting annuals all together.

That farmer in the video said that slugs and snails liked to eat Daikon, but once they chew through the sweet mild skin on the root and they actually ate the inside of the root, that the high sulfur content killed them. I have no doubt that they love to eat the tops and the root skin, I’m just wanting to confirm whether or not they die after eating the inside of the daikon root. Perhaps that farmer is totally mistaken, but I thought it was interesting and worth testing for myself. Also, some soils are higher in sulfur than others. The sweetest onions are grown in soil with very little to no sulfur. So everything is relative and local.

I grew up on an organic farm on Orcas Island in the PNW and with sawdust on the paths between garden/crop beds, garter snakes, beetles, and other slug and snail eating critters, slugs and snails were never a problem.

I highly recommend not using the Sluggo or any other iron phosphate slug and snail killers. The iron phosphate by itself isn’t toxic to anything, (including slugs and snails), they all add EDTA to it to make it toxic and in turn, it also makes it toxic to dogs, cats, birds, earth worms, etc.

Here is one of many websites to read about it (and a Google search can lead you to many more).

https://www.loghouseplants.com/blogs/greengardening/2015/11/we-need-safer-slug-baits/

Not everyone can have or wants to raise birds to help out with keeping slugs and snails in check (a garden duck is awesome and they don’t tear up the plants like chickens). But there are many other techniques and methods that can help make it much easier and far more manageable. The above link I shared covers a few methods.

There are many other sites that cover other control methods. Kill boards in and around your garden are easy and can serve as something to step on if things get muddy in the rain. Spray bottles with soap, salt, instant coffee can be handy and wipe out the tiny ones really fast. Beer traps work, coffee grounds, egg shells, etc. Also, not having anything but kill boards to hide under. No leaf mulch, etc.

Good Luck!

OMG. Thank you, for the heads up about the EDTA.

In response to the slug issue...there are several remedies you can try. The best one would be ducks. Muscovy ducks. But they will eat most everything else, too. I put boards between the rows of veggies, then in the early day, turned the boards over, used a large scraper and scraped the slugs into a 5 gallon bucket. Fed the slugs to the chickens, ducks & turkeys. BTW...turkey poults will eat Gypsy Moth caterpillars by the ton!

Crushed egg shells work very nicely. Spread them around each plant and they deter slugs. Also...DE will work. But you have to renew the DE after rain. Not a problem here now in the north east since we are short of rainfall!

If your compost bins are close to the garden, think about moving them. Compost bins are thriving incubators for slugs. And they can crawl far distances for fresh food!

Beer traps will work but you have to set them up correctly. The edge of the trap needs to be at soil level. The slugs can't resist beer and will drown in the beer. Stinks if you don't empty often, but once again, feed the chickens with the dead slugs.

JFYI...dried coffee grounds will repel ants. Just dry them in a container (pie pan works nicely) and then spread the coffee grounds directly on the ant hills. They vanish. DE will work well, too!

One more thing. My uncle bought in MOO DOO compos (bagged product) and found there were a LOT of slug eggs...that hatched and ate his garden. He stopped buying that product and the slugs went away.

Good luck!!!

Slugs likes to eat greens in decomposition first. That’s why they get attracted by compost. If they have no green in decomposition, they will eat the weakest plant (transplant, young plant, stressed plant, etc...). So just add some of the food scrap food to your mulch and they will eat it first.
Slugs are vital for a healthy garden. They help to bring back fertility by digesting the food scrap and they attract beneficial predators. Their mucus is rich in nitrogen. They eat fungi but they don’t digest the spores, instead their digestion activates the spores witch means they helps to spread the mycelium.
Work with them and they’ll become an asset

I have little experience with slugs, but I think I am going to get more this year. I just want to make a clarification. Leigh seems to insinuate that it is the leaves that attract slugs and woodchips do not. I have seen personally and in other posts here on Permies where the slugs invade the woodchips just as much. I think your best bet (as other people have already said) is to work to balance things ecologically. If you do that, then you have a bunch of helpers to keep the slug population down. If not, then you have to do all the work yourself.

My last house had a garden that had a huge slug problem. They seemed to avoid tomatoes, but ate the heck out of my hot peppers. I think I got one good habanero that year. They devoured young bean seedlings and leaves, but by and large left the actual beans alone. They didn't seem to bother zucchini or bac choy, but other greens were demolished. I put down boards and then flipped them over in the morning and killed them. Beer traps were too much trouble and eggshells, copper etc didn't work. I also planted a ton of marigolds as a trap plant, which seemed to be the #1 slug food choice, ymmv. Good luck!

Matt McSpadden wrote: Leigh seems to insinuate that it is the leaves that attract slugs and woodchips do not.

Not an insinuation; just a personal observation.  To add to that, for every one slug I've seen in my wood chip mulch, I've seen dozens in the leaf mulch. I'm guessing this is because the dried leaves are curled and offer such nice hiding places.  

This is how to make your own nematode potion!

For easier murdering, I place pieces of plywood around the garden, starting in winter. On a regular basis, I turn these over and kill any slugs hiding beneath, using any sharp instrument or rock to cut them in half,or just squash them if tiny. In early spring, they are tiny, but now, there are some bigger ones. The idea is to cut down the population of slugs. I also have a large rosemary plant that needs constant trimming, so I place sprigs of rosemary around the vulnerable plants, to repel slugs. I also use slug bait - again to cut down the population. I just tried copper collars on cabbages, but feel the money could have been better spent. It seemed to work, partially, but not entirely. Another hiding place for slugs is among rocks that are piled up. Note: I have had no luck with beer traps. Oh, and I have gone out in twilight and hunted in the grass, especially in summer when they are large enough to see easily. Good luck!

After giving up on my winter gardens because of small snails and slugs,my slug predator arrived to control them.
when I stopped using the D.E, eggshells etc..for a season or two I started noticing a long snail and less slugs crawling up the side of the house.
These snails turned out being the Rosy Predator snail and they love slugs. even their newly hatched babies go after slugs of all sizes. I started locating them together when I would see them so they would multiply and it worked very well. I can now plant my greens and such and is very little damage.  I cannot believe these snails are not sold to gardeners, they are so very efficient.

I thought this sounded like a great bit of knowledge, until I found out these snails are only found in tropical and sub-tropical places. Maybe we have a similar natural predator in the north..

I wonder is various mints would act to repel the little monsters? I have a big ole patch of spearmint that I could cut and scatter throughout the garden...It's worth a try

I’ve found needle ants have been very effective at controlling slugs, hammerhead worms, and fire ants in my garden.  The needle ants can’t do anything about the adult slugs, but eat their eggs and hatchlings.  It took a couple of years after the ants appeared for all of the adult slugs to disappear and they weren’t replaced by the next generation.  Ditto for the hammerhead worms.  It only took them a year to clear all of the fire ants out of my garden and hoop houses.  Slugs used to be a big problem on my strawberries, but now I rarely see a slug on them and the main pest on the strawberries now are pillbugs, whose armor plating deters the ants.

I am going to try hazelnut shells this year around my slug loving plants here in PNW.  Anyone have experience with these?

Agree about red and purple things
They won't climb up Cucurbit stems once they become hairy and prickly - and my cucurbit fruit never sit on the ground

For baby plants, I do think putting them up high on metal tables and planting them out when they're big enough to defend themselves is the best way ( did same for climbing beans this year and have finally got some climbing beans - Even peas - I just empty  whole window boxes-ful into the garden so as not to disturb the roots)

The discussion seems to have veeered onto slug control, Concerning that, I read that :
- Slugs are useful and neccesary in the garden - their slime is a fertiliser or something
- Many slugs eat other slugs
- Slugs' preferred food is mushrooms, so the more mycorrhizae  you've got growing in your healthy soil the more they'll leave your veggies alone (cf discussions on woodchips)

And of course we all know about balance and natural predators.

One side note that may be of interest is that the slug to snail ratio in an ecosystem reflects calcium availability, as the snail’s shell is largely calcium. They seem equally problematic (or beneficial), but which terrestrial Gastropoda you see does tell something about your soil and garden ecosystem.

Slugs are horrid little things and I cannot deny that I have a terrible fear of them...I literally gag going near them. I have a small little garden and am trying to grow some vegetables and flowering plants but they are completely destroying them. There is no space for ducks and I live in an urban area where I cannot remember the last time I actually saw a beetle let alone a frog. However...I still cannot bring myself to killing them and I resort to just throwing them over into the empty space behind my house. Yes I know, that is just moving the problem and creating another imbalance...but what am I to do with this fear I have of them? Is there any other suggestions of how to reduce the slug population without murder (or atleast inhumane murder)?

With a very small garden I might consider the copper edging trick with wire along any raised beds or pots. Martha Stewart did a penny ring glued around her pots. I do not like to do it, but with invasive European brown slugs I will put a sharp stick through the back of their head if I have no fowl to feed. This seems to kill them immediately.

randal cranor wrote:Howdy,
I don't remember where I read it, but my slug deterrent over the years has been crushed egg shells. Slugs can't handle the sharp edges. ...

When I lived in town one year while doing major repairs to my house, and I was container gardening the front asphalt with cherry tomatoes for the whole street, I had a neighbor across from me who worked at a diner and brought me buckets of eggshells (and helped himself to tomatoes)

I used the eggshells in the backyard and worked them into the ground along with the contents of city compost bins as well as a good layering on top. and I only grew stuff I wasn't eating, hosta la vista!

For the benefit of the slumlord, since what has been there previously was a massive quantity of dog poo, I took pictures of before and after
When he complained upon leaving I sent him photos

So if in short supply of eggshells try visiting the back door of a local breakfast place and offer the cook a few dollars for each full bucket of eggshells until you have enough And get them spread and hosed down before they stink

Ben Zumeta wrote:With a very small garden I might consider the copper edging trick with wire along any raised beds or pots. Martha Stewart did a penny ring glued around her pots. I do not like to do it, but with invasive European brown slugs I will put a sharp stick through the back of their head if I have no fowl to feed. This seems to kill them immediately.

I did used chunks of copper piping until I did my next load of scrap metal

Ben Zumeta wrote:One side note that may be of interest is that the slug to snail ratio in an ecosystem reflects calcium availability, as the snail’s shell is largely calcium. They seem equally problematic (or beneficial), but which terrestrial Gastropoda you see does tell something about your soil and garden ecosystem.

Interesting... so I ought to go bring a few lidded buckets for crushed eggshells to the nearest restaurant, flashing cash for full buckets!

I get salamanders
Perhaps you know eco wise what that means?