Using hydrated lime against slugs

I have always had a big slug problem here, lots of mulch ,organic matter etc
Provides good habitat.
I have used the iron phosphate in propagation areas, but it can be expensive .
Last year I came across an "old "article from I think the USDA on slug control,
Using hydrated lime dust.
I put some hydrated lime in an old garden duster with an extension pipe on the discharge and gave it a worl under some seed flats that were being eaten.
The slugs came out like they were on fire, but did not make it far.
Just a very light film of the dust was enough to make them give up all their slime, makeing it only a few inches befor they could move no more.
Was “almost” enough to make you feel sorry for them. :slight_smile:
As the soil is acidic here, lime is ok.
The amount I used is very small, just a barely visible layer of dust.
Do not breath the dust , or get in eyes.
Pickling lime comes in small sizes in the grocery store works well.
So last year I wooped them
And I am not sharing my beer with them as some people do !


Save your beer! My go-to for slugs has been a salt shaker, as long as you’re willing to address them “in person”. Same kind of deal- almost enough to make you feel sorry for them. I think ashes, and maybe diatomaceous earth are also suggested for them, but I haven’t tried those.


Not sure about saving the beer, just don’t like to drink with slugs.
The salt goes good with beer ,on a hot day, and may be better than salting the earth.
From what I saw the hydrated lime is the trick


Quick lime (hydrated) is cheap and is used to make lines in baseball fields and therefore fairly widely available. I used to use it for rapid pH change- I later learned it can be dangerous for plants. Fortunately that turns out to be an exaggerated danger. Defy the book and you sometimes learn something. Of course there are also sometimes consequences.

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Dangerous to plants ?
Please explain …

I was concerned it would burn the foliage on tender seedlings ,
So I purposely wet the leaves an dusted some as a test
So far no ill effects
Mostly I use it under seed flats where the slugs hide, and a perimeter zone.
A 50 # bag is very cheep,compared to the comercial slug bait.
But more than most people need , so that’s why I mentioned the small container of pickling lime , 1 # goes a long way


Thanks Hillbilly,
Did the article mention using it on the plants or on the ground around the plants? And how thick a coating was needed? I have a small bulb duster that could work with this when damage shows up.
I’ve used the slug pellets sparingly with good effect, usually after a rain, about once a month. Consistency pays off.

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Sorry , can’t find the article .
Don’t remember details well
It was from like 1917 ,or so…?
Befor the lobbyist had much influence on research .
The amount I use is ,as stated above , a “very” light dusting.
Not really enough to notice as you would walk by ( not white)
Just a barely visible layer of dust.
Hydrated lime is very caustic,and potentially hazardous to handle.
Caution is needed.
The long term effects on the system is benign , or beneficial


Using too much can burn plants. Hydrated lime has come into favor in recent years. Other form of lime can take 6 months to work. Many lime lawn products are now using hydrated. So it’s as dangerous as using too much chemical nitrogen fertilizer, you could burn the plants.

In my opinion lime is way overused, but that is for another discussion.

Almost all fertilizer and pesticide companies now sell hydrated lime for garden use.
I hardly ever need it, if I do, I use wood ash.

A soil science teacher stated that hydrated lime mixed in soil immediately before setting in plants can burn their roots in a class I took decades ago. I think I’ve seen it said in the lit since but if you are interested you can do a quick search and let me know here. I’ll probably look it up later.

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It has a very high PH similar to lye. Say goodbye to the snails. I’m not sure if it will rust metal the same way salt will. I believe it has a neutralizing value about 50% greater than powdered lime stone. The hydrated lime I have seen is also very fine and produces a lot of dust that I would not want to breath.

I found some references regarding putting it in the planting hole for flowers. I don’t know if it would damage fruit trees if it was placed in the planting hole,but considering the high cost of fruit trees I would not take a chance especially if ground limestone was available unless I wanted to experiment.

I thought the main deal was it was quicker, not ultimately that much more sweetening. Even if it is 100% limestone I don’t think that could increase ultimate potency more than 20%, off the top of my leaky head.

i use DE. its edible, ph neutral and a dusting around plants is like putting spike strips down! cuts them up then they die of dehydration. i use a herb shaker container to put it out.

Yes. Alternately, it is a poor choice in western states.

Do you also have issues with Armadillidiidae? My soil is high in organic material and I use mulch also. Slugs are not too bad here but Armadillidiidae are horrible. People without high populations will tell you they only eat decaying plant matter but here they will eat fruit, seedlings, and iris rhizomes without any preexisting damage. DE doesn’t work, sluggo plus is expensive, and the orange peel trick only works on small populations. I’d love to hear how you are dealing with them if they are a problem for you also. thanks for the tip on the lime for the slugs. My soil is acidic also so I will give it a shot if I ever get high populations.

Why don’t you address the real problem: too much organic material in your propagation soil !?

If it helps you dont need to user beer in your taps. Molassas, yeast and water will work just as well.

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i had a serious problem with slugs. 3 different species and DE does work and works well. you have to reapply after a rain but if you apply in the same circle around the plant it builds up and makes a barrier they won’t cross.

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I live in Southern CA (San Diego), for slugs and snails I spray them with 30% solution of ammonia. I spray with Solo 1L hand sprayer over area that I see slug/snail, and area is cleared. Best time to spray is early morning, especially if there is any moisture on things. DE did not work due to regular moisture from coastal influenced weather.


It’s my yard not my propagation soil. I propagate in a sterile growing medium.

I was saying DE doesn’t work on Armadillidiidae.

sorry. read it wrong.