I don't think so... at least the eggs might survive.. in colder zones there are plenty of slugs

I agree with Heathen. I don't know if the adults die in the cold or not, but I doubt it. I am in zone 5 and I saw several slugs on my driveway after 5F temps.

Even if the cold does eventually do in the adults there is no shortage of slugs in the spring. -20 is the average coldest temps here and Southern Cali doesn't get that cold so I wouldn't count on a cold snap doing anything to thin out the population.

Cold will not reduce your slug and snail population, much. If cold was an effective control of these buffers those of us in the northern tier of the USA and those in Canada would not see them, but we do so it isn't.

Now THERE'S someone who is determined to find something good about all of that miserable weather in her location,lol! Wishful thinking, I am afraid. It might slow them down or delay their emergence somewhat.

THAT would be a good thing, right?

I was hoping the cold would kill weeds... but NO! :o(

I grew up in Indiana and Wisconsin, and we didn't have the same snails or slugs that we have here:

http://www.stthomasday.org/Science%20Festival/images/snail%20on%20hand.jpg

also they aren't as much of a problem there as they can be here, so I was hoping that California snails would be more sensitive to cold.

But the gardeners on the California forum agree that the cold won't help much, and google says the same, so I suppose I'll just muddle along. The sluggo went down this morning.

As far as a silver lining, at least in California: Stone fruit crops (including cherries) will benefit from this. We should see good prices on all those yummy peaches and nectarines.

Hot dry weather is more of a problem for the slugs.

Your California slugs/snails might not survive the long periods of freezing weather in the cold areas of the country, like New England, or the upper Midwest, but they should have no problem with the relatively light frosts and shortish time frame that you will be getting. Snails just shut themselves up, deep in the mulch or grasses, and slugs burrow deeply. I wish it made a difference, as the very mixed winters (days in the 60's-70's and the next day/week, 30's-40's, nights from high 40's to mid-teens, with an occasional below 10) we have here in SC don't kill them all off, either. I do know that the ones I used to see in VT were a lot smaller than the ones in San Francisco or WA, so that might be one effect of freezing, the big ones get done in, but some will survive and grow, and eat.

No. If it did we wouldn't have any. But ground beetles do, big time. Just provide a natural mulch to give them cover and they will reduce your slug population progressively. Regards, Petr.