I've never heard of adding vinegar. I mix 15 parts water to one part household ammonia and go out at night. Even 20 to one works if you have weak slugs. I have a few different types of slugs, and notice that the big gold ones are pretty tough...I should probably even go with ten parts water to one ammonia. Yes, you must make direct contact with a slug for it to work. You can, however, drench the bases of hosta in the hopes of taking out some hiding slugs or slug eggs in the process. In the Spring, I always find them lurking there just as the hosta eyes are coming up. So Spring is a good time to do the drench.
Best times are early morning, after a rain, dusk, and night.

For years I tried Sluggo (iron phosphate slug bait) and found it to be completely ineffective in my garden. It works for others, but I watched my slugs bypass tons of it for the plants. I find daily slug hunts much, much more effective. I spread out little pieces of lettuce around the garden which attracts them, and that's how I find them easily when I go out with the ammonia in the spray bottle.

I've heard other slug pellets with Metaldehyde, such as Ortho Bug-Getta, are more effective, but I can't use those poisons with dogs around.

Yeah, I don't think I'd use vinegar.
Vinegar is an herbicide and could damage your plants.

I have a 15 gal sprayer on wheels that I hook up to my garden tractor. (A birthday present from my hubby a few yrs ago) Late at night, (1am-2am) I go "slugging."
My hubby has it all ready for me when I get home from work. He puts 15 gals of water and 1.5 gals of ammonia in the sprayer and away I go. I totally drench the plants. I also spread Sluggo every 2 weeks or so.
I buy Sluggo in bulk, like I do most everything that I buy off the internet. I buy it in 40 lb bags. I use too much of it and am too cheap to pay nearly $10 for a 1 lb can.
I've never used a vinegar solution.

yeah melissa informed me of that earlier in the year when I was asking why are brown spots showing up on my heuchera after using vinegar lol... the iron phosphate baits worked well for me this year..
John

Thanks for your comments. And I did wonder about the vinegar, some postings read like you could use either this or ammonia.
So, ammonia solution at dusk/dawn, directly on the slugs. And I liked the idea about the trapps or feeding places.
Well, to a great leafy season 2011, bye, Lin

The bad thing about ammonia, and probably vinegar too, is that it hurts the toads and earth worms which are good for the garden. Toads thrive on slugs. A few years ago I was spraying and there was a big toad that got sprayed too.
He acted like he was on fire. I brought him inside and gave him a bath,
(Yeah, I really did)
Let him back outside and he hopped away.

I had that happen once too, Sassy, and it traumatized me. Almost as bad as when I came upon the garter snake eating a toad. I rinsed my toad off with a hose and he seemed ok. After that, I was less liberal in my spraying and was on the lookout for them. I don't worry much about the worms, as they are usually deep enough in the ground not to get spritzed. If you do the soil drench, then yeah, it's gonna hurt the worms.

That's also where the lettuce traps work great- I just place them in strategic spots and the slugs flock to them in droves. Kind of like they are supposed to do with beer, but don't, in my garden. If you turn the lettuce over, there will usually be some on the other side too. Then I just walk around with a hand held squirt bottle and target the ones on the lettuce. If it's a rainy day with high slug activity, I will use the pump action sprayer with a wand and insert the want into the centers of certain hosta. There are some, like Regal Splendor, that the slugs like to bore holes into the petioles, causing them to collapse. I hate going out and seeing that! The sprayer with the wand helps a lot with that.

The lettuice bait areas will go out this afternoon and I'll look for the slugs tonight! That sounds like such a good idea.

It helps to read all the posts under each subject. You often find out things you didn't know about.

Connie

Ahhh, an eternally ongoing discussion of this hosta problem. Glad to see it's still up-front in the discussions.

After last summer's disaster of being called out of town for a sudden and unexpected death in the family, at the worst possible time for slug hunting, early July for us here in zone 4b, and returning to find our 2 acre >1000 hosta garden looking like Swiss cheese, I embarked on an epic research project about how to avoid this from now on. We love to give tours of our garden, so this was a priority.

After literally hundreds of hours of reading, I decided to go chemical. Yes, the beer bait traps that I used after returning home last summer were so amazing, but keeping up with them in this size garden were untenable.

So now, there are, basically, two choices: Iron Phosphate or Metaldahyde based products.

Iron Phosphate claims environmentally friendly. Metaldahyde claims better effectiveness. Pros in commercial crop fields that are also prone to slug damage use, by and large, Metaldahyde based product.

This year I used both, with no noticable difference. Certainly, I saw no difference in wildlife population, a major concern to me. In fact, there was a record number of tree frogs here this year, so they must have enough other prey to thrive. Other frogs, turtles, snakes, birds, and so forth, were all normal. Actually, I had a record number of some species of birds, all insect eaters. YAY!

Now I'm expanding my research to a second ingredient found in some products. This is about cutworms and the like. OK, slugs cause most all of those roundish holes in your hosta leaves, but what about the long oblong cut paths between the veins? Cutworms, and the like.

A few of the products available to do in the slugs include an ingredient to take care of cutworms, et. al. so I'm studying this now.

The ingredient used to do that is reportedly hard on honey bees, and that's a concern to me, of course. I don't have enough answers about that quite yet, but what I know now leads me to believe that the active life of the ingredient that drops cutworms is short enough to be safely applied at dusk when the honey bees are gone, and when they arrive the next morning are good to go.

Since there were no bee hives close enough to me this year to test this, I remain clueless and hopeful.

Bottom line? My wife posts pics of our gardens on another forum during the past few weeks and others on said forum are in amazement that ours are still in show quality.

Nuff said?

hillbilly, awaiting tonight's predicted frost, wishing it weren't so, but it's overdue, on average . . .

Hi Hillbilly,
sorry to read about the death in your family.
Here 2 additional commemts :
1. Costs : I bet the commercial growers use metaldahyde products to fight slugs because of cost. I with only 250 hostas still like that Buggetta is only 1/3 the cost of Sluggo.
2. Know that there was success and need for it : I like to see if I hit any slugs, that is if there (still) was any need for it, metaldahyde use let the slugs leave a slime, after Sluggo the treated slugs hide to die.

Bernd

Just a quick addition to the topic. A couple days ago I embarked on a slug hunt. In an area where I had not put Sluggo down I sent about a hundred to meet their maker. In an area where I have been faithfully applying Sluggo I found two.

More on topic, here's my take on ammonia. First, ya gotta hit 'em with it, and so many are hiding. Second, the dosage is iffy, at best. The 'Butch Ragland' claimed rate, using a garden hose-end applicator is impossible. I did the math, called the companies selling said applicators and found the maximum rate possible was noteable less that that commonly recommended. I then found some trial slugs, placed them on the potting bench and sprayed them with the max a garden hose-end applicator would allow. They all lived, drat.

I was very interested in this as we have too big a garden to use manually mixed 2 gallon sprayers often enough to even begin to hit enough of them exposed enough to make a dent. Besides, ammonia is so cheap, as am I ;-)

Bottom line is that the combination of iron phosphate and metaldahyde stuff kept our garden show worthy right into September. Also of note is that all known wildlife is still plentiful and flourishing, including a bumper crop of those exceptionally loud lil' teeny tree frogs, and all three of our vole-patrol cats are still alive and SASSY, so much for the OVER warning about pet hazard.

If you rEAlly dig into the warning label material, you'll find that you'd hafta leave big piles around for them to gorge on to kill 'em.

Yeah, I don't like chems but do take an occasional aspirin or penicillin shot.

Now, let's get a big huge comprehensive pesky 'no-holds-barred' thread to finally squash the nematode issue, shall we, please?

Last call request: Will everyone who can share where to buy, in bulk, like 40# bags, of iron phosphate or metaldahyde based stuff that also has the third ingredient for cutworms, et. al. ? I've found a retail source for metaldahyde stuff, but not a source for that and/or iron phosphate with the cutworm et. al. included, waaaaaa.

Now's the time for planning, eh?

hh

I do not have any source for 40 lb bags of Ortho Bug-Geta Plus, but for my 250 hostas I would never need 40 lbs, I am happy with 9 lbs max per year because not all areas are infected with slugs, and the need decreases over the years.
I buy my 3 lbs jugs of Ortho Bug-Geta Plus at Home Depot for $ 9.38 each. Walmart and Lowes are more expensive. Sluggo costs 3 times as much.

All the details of this insecticide you can read via Google. On the jug the label shows that it kills also Cutworms, and that it may be used around vegetables! From the label :
Attracts and Kills Pests : Snails $ Slugs Plus Ants (...), Armyworms, Crickets, CUTWORMS, Earwigs, Grasshoppers, Millipedes, Pillbugs & Sowbugs.
Where to use : - in ornamental gardens..., - Around vegetables.
Have a good one!
Bernd

This is related to slugs, so I want to ask. I wonder if someone could address the problem of many small holes in leaves. Those holes do not seem to come from slugs, because an application of Bug-Geta does not produce slime and dried up slugs, but holes still form. This is a problem with a few hostas I have, all with thin leaves. In the past I thought I read that flying insects cause that, moth? Thanks!
Bernd

Bernd...
Are you sure it's not the results of heavy rains/hail?