mulch versus slugs

Hello Patrick,
I have a question for you. I mulch with free wood chips every year. I know this is good for the soil food web, but I also feel it harbors slugs. What are some good permaculture techniques to deal with the slugs while nurturing the soil?
Thanks
John S
PDX OR

I second this question, and please don't say beer because here on Whidbey Island that just creates drunk slugs who come back for more. Persistent little buggers they are!

Hello,

Yes, slugs and mulch is one of the perennial questions. Permaculture started in Australia, where slugs aren't such a problem but drying soil and soil exposed to excessive sun are big problems. Here in temperate climates conditions are different and slugs are a much bigger problem. I feel that importing Australian permaculture wholesale rather misses the point. For me the basis of permaculture is tuning into the unique characteristics of the land and the people in question and designing for them, not faithfully following a prescription. Myself I use very little mulch. Mostly I just mulch with well made compost.

Here I'm following Charles Dowding, a famous no-dig gardener here in Britain. He started off his gardening career some 25 years ago very much inspired by Ruth Stout and her deep mulch method. He very soon found you can't get away with that in a place where slugs are a problem and adopted a compost-only approach to mulching. He mulches the whole of his garden with 5cm (2in) of compost every autumn. By spring it's well incorporated into the soil and he has a slug-free habitat for his vulnerable little plants. Putting compost on in autumn is against all the theory, which says the nutrients in it will be leached out by the rain come spring. But he reckons his soil is so full of life that they all become bound up in biological form and there's no significant leaching.

Probably the best way to control slugs in the garden is with ducks. Let them have free range in winter, when there are no crops they want to eat, and by spring there will be no slug eggs left at all. The only slugs you'll have will be ones which come in from outside. You can then let the ducks into the garden when you're there and if they stop eating slugs and start eating your crops you can politely usher them back into their permanent home. You may have to net some of their favourite nibbles, eg young brassicas. You need to get the right breed. Most ducks are vegetarian but Khaki Campbells are omniverous and love slugs.

Frogs are the next best. They won't eliminate slugs, as no wild predator eliminates its prey, but a good population of frogs makes a big difference. All you need is to provide a pond with shallow water, less than 60cm (2ft), and they'll come in if you live in a rural area. It can dry up after the frog breeding season is over. In suburban and urban areas it's hard to build up a frog population, though, as cats will kill them.

Personally, I can't keep ducks as I'm often away from home, nor frogs because of the local cat population. I try to minimise slug problems by growing crops which avoid them, including perennial vegetables and spring greens (collards) which, in our mild climate you can start off in autumn, when slugs aren't a problem, and mature them in spring. When I do have some vulnerable crops I sprinkle a cordon of bran around them. Slugs simply love bran - they'll go for it in preference to green vegetables - but it's fatal to them. It dries up their slime and they swell up and die. I just use it to get the plants over the first few vulnerable days when I plant them out. I don't like to use too much of it. After all it's food and you could use up more calories of bran than the calories in vegetables you save, which seems to me to miss the point rather.

Has anyone else got good tips?

Thanks Patrick. We can't have ducks yet either but I think we could pull off some small frog ponds, and I like frogs! We have tried with zero success beer, copper, coffee grounds, and even spearing one live slug to the ground so its buddies could eat it(we read it works, but it doesn't and is just morbid)

Suggestions:
-Plant much and sacrifice much.
-Learn to grow what slugs don't like.
-When you start to see a slug go to work on a mature plant, pull it and its comrades and eat them (the plants not the slugs).
-Transplant susceptible plants like Basil, making sure the slugs can't reach the leaves when they are planted.
-Iron oxide used in organic farming as bait when things get tough.
-Animals that eat slugs but not vegetables, or eat slugs given to them away from vegetables (chickens, ducks).
-Overturned black bucket, slugs congregate there in daytime, you pick them away.
-Beer works for me. Lots of dead drunks to add to the compost.
-Dry weather
-Lots of mulch. I have no evidence, but it seems that they don't tend to move around a lot when you have rich soil, decomposing things, and lots of mulch (I use straw). It's like I see a slug from time to time, but their presence has near-zero effect on the plants, so I just leave them there. And I have a very shady, wet yard to work with.
-I hear lizards can help, I have a bunch running around, but I never see them eating anything, much less a slug.
-System biodiversity and balance in general.

Best,
William

Patrick Whitefield wrote:The only slugs you'll have will be ones which come in from outside.

I live next to many acres of old growth forest. It's ALL outside and the slugs and snails keep coming in waves like a zombie pic. Mulch/no mulch is irrelevant at this level of infestation. Things like setting out beer and planks are like trying to hold back the ocean with a broom. They climb right over coffee grounds. The only thing that seems to work is liberal dosing with Sluggo (iron phosphate) whenever there are seedlings, because if I don't they seedlings are ate to nubs as soon as they sprout. As a result, my garden is literally littered with snail shells.

Supposedly thrushes like robins and bluebirds will eat them, but although I have a whole lot of them (and they patrol my garden daily) I haven't seen one eat a slug or snail yet.

On the upside... I don't have any calcium deficiency problems!

Rumor has it the onion family helps repel slugs.

Haha! We live in Australia and it can be SO wet, last year we had millions of frogs and zillios of slugs! And we have wild ducks and they are worse than slugs, so take Mike's advice literally: only let the slugs in the vegetable garden when it is empty!!
There is one thing which really seems to work (I haven't done it and now we're going back to dry conditions) that is a copper band whith sticky tape on the back. The slugs get zapped when they try to cross it. However you must have a timber edge around your whole vegetable garden. You can't do it around each individual bed, the costs would be prohibitive. You can try electrical wire as well, don't ask me detais.

I let my chickens and geese rotate through the gardens.

We do have a vigorous winter garden season so I don't want the birds in there for very long because I have seeds to plant. I let them in around August - it is a between time for us and I just let them tear the ground to pieces. Then I go back to my heavy mulching with green grass clippings.

I do wonder if the frogs are helping - I didn't know they ate slugs. We have a little (300-400 gallon) pond and it hatched out three times this past year - had to be 500+ tadpoles each time - the were a bunch of them. So that may have helped keep the slugs down a bit too.

We don't use chemicals of any kind so something is working - I just don't know exactly what it is.

Paula Edwards wrote:
There is one thing which really seems to work (I haven't done it and now we're going back to dry conditions) that is a copper band whith sticky tape on the back. The slugs get zapped when they try to cross it. ... You can try electrical wire as well, don't ask me detais.

I've looked at that, and yes, it's extremely costly. The downside is that the once the copper oxidizes, it ceases to work, and copper oxidizes very fast. So you have to either clean and polish it or replace it. Also your band has to be large enough that slugs can't step over it, and they are smart enough to do it. My slugs max out at about 2" but some folks have 4-5" slugs and that means they need a 5" wide band of tape clear of all vegetation, leaves, etc. In the end, I decided that the cost + maintenance effort was much higher than the reward. I think it would work well for prized plants in planters and pots but not so good for out in the garden.

I saw a video of an electric wire experiment. It took the slug about 3 seconds to figure out how to step over it.

I also investigated reports that slugs won't cross sandpaper but I could never get the kind of details that made me think it was anything other than wishful thinking -- certainly not the kind of details for me to figure out what grit sandpaper and find a waterproof version and staple it around all my raised beds.

It's really interesting to hear all your different experiences with slugs and ideas for getting rid of them. I don't think there's any one method, or even any one package of methods, that can be recommended as THE answer. Every garden is different and every gardener is an individual too. What works for me doesn't necessarily work for you, even if you live just round the corner from me.

This is one of the keys to the way I teach permaculture. At the beginning of a course I say to the participants, 'I'm not here to give you the right answers. What I want to teach you are the right questions. If you start out with the right question you have a chance of getting the right answer. But the answers are different in every case.'

For somebody with a small yard, and no poultry, one solution is to throw every slug/snail you find atop the compost pile. They will find plenty to eat, and speed up (and enrich) the composting.

If they have plenty to eat in your compost pile, they should happily stay there, leaving your garden alone.

The problem becomes a solution.

For slugs I try to encourage garter snakes which eat slugs. For the snakes I lay out flat stones, boards, and rock stacks/piles, and they definitely use those.

I also keep an old pair of scissors by the back door, and take them with me every time I go outside. If I see a slug I cut it in half. Kind of gross but you get used to it, and it does really help a lot. I like the scissors because it kills the slug no matter where it is - even if it is at the top of your plant. Also I can get even the tiniest slugs.

I don't kill the native slugs though - those mainly eat fungi so there is no need to kill them.

I have had good success with a spray made of garlic, hot peppers, and water, blended together and then applied with a spray bottle. Get the hottest peppers you can find. Works great, apply once a week with seedlings less when the plants have grown and have a thick wax coating to protect themselves.

Thanks for the info with the copper band! I really contemplated about buying it.
There is a method, but it is not for the faint hearted (and even slugs play an im,portant role in the garden): You collect slugs put it in a bucket,
pour boiling water over them let it stand (I think for days) and then water your garden with that. Ihaven't tried it because it seems to be very cruel (I'm not vegetarian BTW).

Wow, these are some awesome slug remedies. I'm inclined to agree with you, John, about putting them on the compost heap. That's where I put them. It makes real sense that they'd rather stay in a warm heap of food, no crawling required, bed provided than go back out into the garden. I mean wouldn't you?

My sister uses scissors too, Dave, to leathal effect. It does look gruesome but it's effective - if you don't believe the one about just having to put them on the compost heap. In fact the scissor job's not unlike crushing cabbage white caterpillars - do you have them in N America? - which I do with no qulams. It just looks more brutal.

That spray sounds pretty effective, James. I presume you spray it on the ground around plants you want to protect, as a deterrent. How much per area do you use?

What's the purpose of the hot water treatment, Paula, is it to get the nutrients back into the ground or as a deterrent to other slugs? I know the biodynamic people have one where you burn slugs and then spray a solution of their ashes over the garden in homoeopathic quantities. I expect you have to do it at the right stage of the moon etc, and it probably won't work unless youve sensitised the land first with 500 and 501 preparations. Does anyone know?

Patrick Whitefield wrote:Wow, these are some awesome slug remedies. I'm inclined to agree with you, John, about putting them on the compost heap. That's where I put them. It makes real sense that they'd rather stay in a warm heap of food, no crawling required, bed provided than go back out into the garden. I mean wouldn't you?

My sister uses scissors too, Dave, to leathal effect. It does look gruesome but it's effective - if you don't believe the one about just having to put them on the compost heap. In fact the scissor job's not unlike crushing cabbage white caterpillars - do you have them in N America? - which I do with no qulams. It just looks more brutal.

That spray sounds pretty effective, James. I presume you spray it on the ground around plants you want to protect, as a deterrent. How much per area do you use?

What's the purpose of the hot water treatment, Paula, is it to get the nutrients back into the ground or as a deterrent to other slugs? I know the biodynamic people have one where you burn slugs and then spray a solution of their ashes over the garden in homoeopathic quantities. I expect you have to do it at the right stage of the moon etc, and it probably won't work unless youve sensitised the land first with 500 and 501 preparations. Does anyone know?

I don't really measure it out I just add a bunch of hot peppers and garlic to water, blend and spray liberally all over the plants and the surrounding soil. Works well, I once caught a a slug and sprayed it directly with the solution and let me tell you... he did not like it. The slug started to writhe in pain and then its mucus membrane started to foam up like a bubble bath. I imagine he was feeling what you would if you cut up a habanero chilli and stuck it up your nose... or other orifice.

In dry climates, we have also the issue of slugs in mulch, but in winter. Nobody mentioned yet the insects predator of slugs. Ground beetles and firefly larvae love eating slugs, and fortunately they also love mulch.
We had a lot of slugs after mulching (and in lasagna beds), but seems that predator insects are catching up. We tried beer traps, but ended up with more of these predators in the trap than slugs (who knows they may have drown there chasing a drunk slug), so we let the nature do the job, and just protect sensitive seedlings (with plastic bottles and will try with the chili spray)

You may all think I'm a nut but one of the best slug controls is mice. Lay some boards for the mice to live under and they will control snails and slugs.

Air flow is a big factor.
I grow rhubarb and the slugs love it.
The answer is harvest more often and with more greedyness taking all the leaves that are any good redusing the plant to a few sprigs. I used to harvest sparingly and guess what , I make alot more $ this way. Ever get butterfly eggs on your kale? Avoid the problem by harvesting the shit out of it so that any eggs that were laid never hatched before I ate em or sold em.

Just to re-cap that's ducks, mice and punctual, greedy harvesting.

Patrick Whitefield wrote:Hello,

Yes, slugs and mulch is one of the perennial questions. Permaculture started in Australia, where slugs aren't such a problem but drying soil and soil exposed to excessive sun are big problems. Here in temperate climates conditions are different and slugs are a much bigger problem. I feel that importing Australian permaculture wholesale rather misses the point. For me the basis of permaculture is tuning into the unique characteristics of the land and the people in question and designing for them, not faithfully following a prescription. Myself I use very little mulch. Mostly I just mulch with well made compost.

Here I'm following Charles Dowding, a famous no-dig gardener here in Britain. He started off his gardening career some 25 years ago very much inspired by Ruth Stout and her deep mulch method. He very soon found you can't get away with that in a place where slugs are a problem and adopted a compost-only approach to mulching. He mulches the whole of his garden with 5cm (2in) of compost every autumn. By spring it's well incorporated into the soil and he has a slug-free habitat for his vulnerable little plants. Putting compost on in autumn is against all the theory, which says the nutrients in it will be leached out by the rain come spring. But he reckons his soil is so full of life that they all become bound up in biological form and there's no significant leaching.

Probably the best way to control slugs in the garden is with ducks. Let them have free range in winter, when there are no crops they want to eat, and by spring there will be no slug eggs left at all. The only slugs you'll have will be ones which come in from outside. You can then let the ducks into the garden when you're there and if they stop eating slugs and start eating your crops you can politely usher them back into their permanent home. You may have to net some of their favourite nibbles, eg young brassicas. You need to get the right breed. Most ducks are vegetarian but Khaki Campbells are omniverous and love slugs.

Frogs are the next best. They won't eliminate slugs, as no wild predator eliminates its prey, but a good population of frogs makes a big difference. All you need is to provide a pond with shallow water, less than 60cm (2ft), and they'll come in if you live in a rural area. It can dry up after the frog breeding season is over. In suburban and urban areas it's hard to build up a frog population, though, as cats will kill them.

Personally, I can't keep ducks as I'm often away from home, nor frogs because of the local cat population. I try to minimise slug problems by growing crops which avoid them, including perennial vegetables and spring greens (collards) which, in our mild climate you can start off in autumn, when slugs aren't a problem, and mature them in spring. When I do have some vulnerable crops I sprinkle a cordon of bran around them. Slugs simply love bran - they'll go for it in preference to green vegetables - but it's fatal to them. It dries up their slime and they swell up and die. I just use it to get the plants over the first few vulnerable days when I plant them out. I don't like to use too much of it. After all it's food and you could use up more calories of bran than the calories in vegetables you save, which seems to me to miss the point rather.

Has anyone else got good tips?

Great tips Patrick! I'm a newbie at gardening and have basically seen every film with Geoff Lawton to get into Permaculture techniques. This year was the first year where I actually had a garden that I could try some of the things I have seen and read about throughout the years and the first simple thing I wanted to try was "sheet mulching" or "lasagna mulching". The only problem is that I live in Sweden and we have a lot of slugs (which I hadn't thought about) so two days ago I realized I had a huge infestation of slugs in my grow bed. So I went on the internet to try and find something to deal with the problem quickly and basically read about every technique from ducks, frogs and snakes to copper and salt etc. I did however find a new one that I hadn't seen anywhere - coffee. Apparently it's a neurotoxin to slugs and a quick fix, so I bought a pack of the cheapest, ground-up coffee (as I am probably the only swede who doesn't drink coffee and thus don't have it at home).

In the evening as the sun started to settle and the slugs came up to feed on my plants I picked everyone I could find, placed them in a plastic container and then sprinkled the coffee all around the grow bed and around every plant (corn, squash, beans and lettuce). And just to see if it actually works on the slugs I sprinkled it into the plastic container as well. 5 minutes later all the prisoners were dead. This evening I went out to see if any new slugs had come up and couldn't find a single one. So it really worked, my grow bed is now slug-free.

Yeah! I love that Q: "What's a Permaculture Solution to (insert problem here)" you could pick a random principle for response, like "Obtain a yield" I think putting anything in the compost is a default yield- I enjoy, for instance, turning slugs into chicken eggs rather than throwing them on the compost. The chickenshit does more for the compost than a scissored slug I think, more microbiology. ("The guilty slugs were handed over to the chickens for questioning. Gardener Rick was quoted as saying: "the chickens will get it out of them!"). Don't see problems, see opportunities. As we used to say in school, "All generalizations are Bullshit!" You can find sandy soil or pure silt here in W. Oregon, the land of clay. We have nothing but rain and slugs- except in summer which is always a drought. Except when it isn't. This is why I love this work/play. It's not boring.

Patrick, I just watched a you tube video on the “boiling water”.  It actually said to get A bunch of slugs and specifically to gather one or more that have a swollen mantle, which is a sign of nematode infestation...  put in a bucket On top of some cabbage with couple inches of water and seal lid.  They eat cabbage and hopefully really let the infection spread among all of them, then fall in water and die, letting the nematodes infect the water which you then pour in areas affected by slugs..  (straining it)  these are good nematodes that devastate slugs but don’t harm us or are even noticed...
This was recommended DIY of an expensive product that you can purchase that does the same thing.  The nematode practice in addition to a pond to attract wildlife was the key recommendations of this permaculturest..

Hey there John (and others in the PNW area), I'm curious if you implemented any of these ideas and how it worked out for you.

Patrick Whitefield wrote:When I do have some vulnerable crops I sprinkle a cordon of bran around them. Slugs simply love bran - they'll go for it in preference to green vegetables - but it's fatal to them. It dries up their slime and they swell up and die.

Wow, I have to try that. This year was a slug-pocalypse like I have never seen, being unusually wet. They were very happy in the straw mulch I used. Now even the compost piles are shot through with slug eggs, so I need a plan for next year.

My main way to battle slugs is with ducks. When I'm able to free range them, they almost every single slug. Sadly, the ducks keep getting eaten by predators, so I've had to resort to using sluggo on the precious things--like carrots--that my kids really want to grow.

I think I'll try the bran this year!

Fonda Bradley, can you please share with us the link to de video?
tranks!

Hi, I have a suggestion for the slug problem. I've been experimenting with agrohomeopathy and having some success. Not much is written about it yet but that's changing now. For slugs and snails the procedure is to dissolve pellets of the remedy Helix tosta in water, and water the plant (including leaves) and soil. I have only used this one year but it kept them off my greens completely. I only did it a few times through the growing season (not that long here in Canada). It does not kill slugs, it makes the plant not attractive to slugs. No chemicals. I also went sparse with mulch since it rarely gets dry here in summer. The remedy is inexpensive and one little vial should last years for a home garden, but you probably have to mail order.