I look for the first sign of any shoots and then I'm afraid I put down slug bait. I don't like doing this but have had limited success with other methods! I do make sure I put the bait in covered containers though, (small butter/philadelphia type tubs work ok- I cut holes in the sides at the bottom and slightly sink the tub into the ground.
Hopefully other members will give some better suggestions.
I do spray my hostas with a boiled garlic clove solution and this works on them but not sure if ok to use on delphs.
Beba

The garlic spray is fine for delphiniums but not sure how well it deters slugs and snails. Its main use is to keep aphids and the like off plants - particularly vegetables.

You can try ringing each plant with a thick layer of grit which slug wont like going over but if you have a real problem pellets is probably the only solution but please make sure they are the eco-friendly ones that wont kill a bird that eats the dead slug.

Invest in some Slug Gone - its a pelleted product made from sheeps wool that you spread around the base of your precious and attractive to slug plants. Its not cheap, but it will stop the slugs and snails from reaching your delphiniums. Either that or you have to remember to go outside early in spring and putting slug pellets down where the delphiniums are - as the first shoots start to appear in spring, slugs will eat them immediately if they are not protected.

I forgot to do this, this year and mine have been decimated. But I hope they will recover if it ever dries up. [oh how I longed for rain back in April ;o) ]

The eco-friendly pellet that I know is called Advanced Slug Killer and seemd to be available from most garden centers. It is recommended by Garden Organic.

Thanks I'll make sure I get some eco-friendly pellets. I think that last year the slugs did the most damage after flowering as I don't think any of last year's shoots tried to come up this year. Once a delphinium has flower what should you do with the plant? Cut off the flowers? Let it all die away on its own? Continue to protect it from slugs?

I'd be willing to bet that they did come up but got eaten before you even saw them! Slugs are the devil's spawn!
If you cut off the flowers after they have faded you should get a second, slightly smaller flush of flowers. Oh, and copper rings around the young plants help a bit with slugs.

I always go the cheap route for my delphs, Lupins cabbages etc.
I buy copper scourers, unravel them and cut into sections and place round the new plants as they are emerging. For larger plants I undo the copper scourer and pin this round the plants. My Hostas are doing wonders.
I also spread garlic granules / powder round the base and spray with garlic water in times of a quick fix, for when the blighters have crossed bridges to get to their chosen delicacy.

What a clever idea 2nd hand

Wow sounds like there's lots to do, might ward off the vampires as well.

Lol!

Don't forget the copper tapes serrated for snails I'm the same I don't like killing them or having to pick dead ones up. I haven't tried anything so far this year except a year old container of those blue organic pellets which turned into a furry mess and one of my containers was covered in a furry mould. I am having enough problems without this so I have been researching other things for deterring slugs. I liked the sound of the woollen pellets which swell up and sluggy can't get over it or so it says lols!