I have never had a problem with snails, but since planting a large swathe of day lilies I have found between twenty and fifty snails a day in that patch. I have been disposing of every one, to no avail.
Are day lilies especially tasty to snails? Is there something I should be doing to keep them off?
I note you're in Scotland - most of the UK has been incredibly wet this summer, not so sure about where you are, but this has meant an explosion in the snail and slug population. Slug pellets - the little blue pellets of death, metaldehyde based, will do the trick, but don't over apply, just a light sprinkle around the day lillies, reapplied after rain, or after a couple of days if they've all disappeared. Day lillies are attractive because they trap moisture in the base of their clumps of leaves, so its a useful place for slugs and snails to lurk so they don't dry out and can remain hidden. The previous answer mentions copper tape - this can be quite effective most years, but as there are so many this year, its not as efficient currently. You could try both. There's also a product called Slug Gone, made of pelleted sheeps wool which you spread around your plants. Its expensive, and from anecdotal evidence this summer, once its sodden, it acts like a welcome mat rather than a repellant, but works quite well when the weather is dry.
This past spring I had a bunch of slugs attacking my Asian greens. Picking them off by hand didn’t help so I tried Sluggo. After applying I had no more slugs in about a week. Some other options include:
Sprinkling diatomaceous earth (D.E.) around the plants. This has a lot of sharp edges and irritates them when they try to go over it. You will need to re-apply every so often since rain and watering will wash it away.
Copper tape around the bed so the snails/slugs will have to go over it to get to the plants. This works similar to the D.E. but instead of sharp edges it shocks them.
Trapping them is one of the more common things people do but I have no experience in this and have read conflicting stories on what works so maybe someone else can provide some insight on that.
There are marketed in the states, products that are labeled as organic, and contain some form of iron, I have had very good success with them, but I am in a very much dryer location 13"/year total precip, mostly in the winter... Not great at metric conversion but I think 13" is like 1 cubit.
