Even if you deadheaded and you got more flowers, {which I think is unlikely} they would be tiny compared to the flowers you have now, better to leave them and let the birds feed on the seeds, Derek.

I dead head mine, as I get so many flowers its worth doing the 2nd flowers although smaller still look good.

Thanks Derek/Drc i just wondered if i could encourage it to flower more but if dead heading dose'nt work then i think i'll leave it.. besides it is a young plant on its first year of flowering.. .. big thanks again. ;-)

I'd say it does work, actually - Derek's right in that the flowers you get later will be smaller, but rigorous dead heading does seem to make the plant produce more, smaller ones - mine's been going for about 6 weeks and I've been deadheading this year, and I noticed yesterday its showing signs of producing even more. Certainly the bees and butterflies will be very grateful if you can induce some more flowers, lol!

i always deadhead mine until september then leave it to set seed. fewer self sown babies that way.