I have spent the past few hours reading through various posts on nematodes as a form of slug control but I haven't really found anyone who has used them and reported how successful they are as a control for slugs.
We have just over 300 sqm of beds and next season that will be increasing to 400-500 sqm. Slugs have been are Nemesis this season, in spring and early summer we were picking between 1500 and 2000 slugs a day! Just as well we had a host of understanding and not squeamish WWOOFers but the man hours spent picking slugs is ridiculous. We have tried most things;
1) Beer traps work but the number that we need and the frequency that the need refilling is not practical.
2) Copper bands and copper tape work to a degree but only stop those on the surface from getting to the leaves and again are not that practical as the number we would need.
3) Wool fleece, now this did work a treat especially around our cabbages when they were young but as the season has progressed the wool has become slimy and is no longer an effective slug barrier as it was. (I will wash and dry it when the cabbages are harvested and try it again next year) but getting hold of the number of fleeces that we need is going to be a challenge.
4) Sand, roasted and crushed egg shells and coffee grinds seem to work for 'surface' slugs but it does need constant reapplication, that said now the weather has turned wet the slugs have found their way into the sand box that we use to protect the seedlings and the seedlings are taking a battering, but in the summer it worked when the surface of the sand was dry.
5) Fermented slug juice (picked slugs drowned in water and collected in a 25 litre drum until it is full then watered onto the garden), I was very hopefully that this would work and it did on a small test area but when applied to large areas didn't seem to make the slightest difference to the slug population.
6) Rotten wood with the underside coated in sour dough, we found that the rats also like yeast products and would turn the wood over eat all the sour dough over night so this didn't work for us.
7) Companion planing tomatoes did see a small decrease in the slug population where they were used but not enough to protect the young plants and this can only be applied during a shortish part of the season and isn't much good in early spring.
8 ) Dog food in conventional slug traps... it seems that out plants are far more tasty than the dog food!
So from my research it seems that the only things that we haven't tried are iron phosphate (Sluggo I believe is one brand) and nematodes. I have read an interesting article, linked on various other posts, about farming your own nematodes, which seems straight forward enough. However the author of said article also said that the naturally occurring nematodes that 'attack' slugs are only really effective when the slug population is disproportionately high. Commercially purchased nematode are impregnated with a mollusc killing bacteria, which makes them a real threat to the slug population.
So of the two options that we have yet to try has anyone else used them, especially on a garden the size of ours and if so how effective have they been?
Next year we are hoping to produce commercially on a small scale and we really need to get the slug problem under control one way or another, if I have missed out any other effective methods of slug control that might work for us then I would be more than interested in giving it a go, but for now it does seem that nematodes are going to be the way forward for us.
Build snake and lizard habitat. Frogs, toads and salamanders eat them too. Piles of rocks, wood, leaves or any combination of natural materials along with a water feature, will just about guarantee the arrival of some beneficial creatures that eat slugs.
There are very small bantam chickens that are almost exclusively insectivorous. They will eat the slugs and leave crops alone.
I see you've tried a number of measures. If I hadn't read it, few of those things would have crossed my mind, since I don't ever plan to put much labor or resources into slugs. They are the number one garden pest on this wet island and I've beaten them soundly using hungry critters.
We already have wildlife habitats, but here in this part of the UK snakes are rare and there are no lizards. There are already many toads and frogs in the garden, there is already a pond about 3 meters from the edge of the garden. I have thought about putting an other pond in the garden to try and increase the frog and toad population. Hedgehogs are another natural slug predator but we don't have too many of them here.
Location: Victoria British Columbia-Canada
posted 6 years ago
If you were to import additional hedgehogs, would they eat all of your worms ? A wildlife rescue place may have snakes to relocate. Often they are displaced during road building and construction of all sorts.
I want to learn more about slug-killing nemotodes, if they are native in the USA soil (as they seem to be in the UK for sure) and how to grow your own (a cost saving vs buying NemoSlug). Did you try theses nemotodes? Seems your slug soup would grow the nemotode concentration in your soil.
Here is the thread I started on it - with the How to DIY video link.