What's happening to my delphiniums?

I planted delphiniums last year and they flowered very late summer. This year, they produced buds recently, but they have all been decapitated somehow. I don't understand because they are quite sheltered and it's not that windy... Anyway, now all the buds have gone I was wondering if there was anything I coud do to to encourage more buds, like cut them back? :confused: :confused:

 

hi Fiwi yes chop them right back to about 6"... but check what's been eating them, were the stems at top end all black? blackflies can demolish them in no time....put a Systemic down same time like Provado pellets... last all the season....then feed them weekly on high potash...like Phostrogen.
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Ladybird

 

Oh my does that sound familiar - I have lost count of the times that this has happened to my delphs over the years. Lovely budded stem one day, next day, budded stem gone or hanging by a thread. My culprit is snails - they love delphs.

Since thrushes have nested in the garden, I have had the chance to enjoy them and less need for dusk patrols.

I would agree with Ladybird, cut them back to about 6-12 inches - just above a leaf - and then feed regularly

 

I didn't notice any black flies but I do have snails. I will cut them back and be ready for the snails this time!
Thank you ladies for your advice. fiwi