Yes, most likely, but if they are there long enough to turn mouldy, then you;re probably using too many each time. If you put about ten or more n a pot and they disappear, then they've been consumed by slugs and snails - if slugs and snails aren't visiting, they'll sit there and may go mouldy. Or there aren't enough slugs and snails to warrant using that number of pellets - 4 pellets in a small to medium pot would probably be nearer the mark, then you can monitor if they disappear or not....Otherwise, what I do with pellets is sprinkle lightly occasionally, maybe about weekly or fortnightly if the weather is wet and slugs are busy... and none at all if its dry.

I agree with what Bamboo says.

Thank you for your reply and YES I have been putting in far too many pellets then, so less is more, so to speak, I shall only use a few and keep check on progress. Thankyou x

Sorry Loupylou but they should be banned. Too much harm to wildlife and the hedgehogs where I live have all died. I have no evidence but we had a neighbour who used them at the time. The rest of us are against chemical control.

If you still want to use them however try putting just two or three under a flattish stone on the surface of the soil. The slugs will retreat under the stone where birds etc can't get at them. (assuming the pots are too big for any hedgehog to reach on top?) But there are things you can spread round the plant that the slugs won't pass, eg sharp grit, sheeps wool

I never read the small print on box, I will dispose of pellets that are on pots and of what are left and try again with grit etc, next year I shall try the copper tape that goes round pots, Thank you for the extra info,