Yes both lovely plants the deli are perenial and grow everyyear unles we have a very wet winter or the soil gets waterlogedand basicaly just die off as you are probably aware slugs love them so keep a eye on them they are easy to take as cutting now .

I find foxgloves are best treated as bi-annual grow all folliage one year then realy flower the next and just run out of steam/give up the ghost so they are easy from seed and lots to choose from but you need to buy new baby plants in spring if you dont want the seed option

Gg

When my delphiniums have finished flowering I cut the flowers down, they then produce a lovely second lot of flowers, admittedly not as tall but still beautiful in last years seasonal confusion some flowered 3 times, the seeds I collect and throw in any space therefore providing plants for family and friends..

Foxgloves tend to die after flowering. They self-seed well, though not in my garden :(

Treat them as bi-annuals or annuals as you tend to buy them as second year plants that will flower that year.

Am I right in thinking (hoping) that there is a yellow one that is actually perennial?

I know there IS such a thing as a perennial foxglove, Stera, but have no idea what colour it is or where to find one, nor, I am afraid, exactly how hardy it is.

I think you can find one in my garden Gattina. It is supposed to be yellow and hardy - it has gone through this winter anyway, but hasn't flowered yet. I will be able to answer my own question this time next year! I think it came from Long Acre Plants.