Posted: 19/06/2015 at 10:42
Those lupins are lovely, and I quite like tall plants coming forward occasionally in the border - looks less regimented like that. Yes, deadhead the lupins when the flowers fade. Also your Bearded iris, I'd deadhead them too.
Panda's right - that's bindweed - remember the leaves and if it reappears next year you'll weed it out before it starts strangling plants.
As for now I would carefully try to disentangle it from your plants, and cut it down, then get some Roundup Gel and apply it to the remaining bindweed leaves and leave it to go brown and die - it'll take a couple of weeks, but when the leaves are brown it'll indicate that the roots are dead too.
If you try to pull it up before it's dead every little bit of root left in the soil will grow into a new plant.
The purple flower is your aquilegia